Which number will take the place of the question mark (?) in the following series?

Which number will take the place of the question mark (?) in the following series?
निम्नलिखित में से कौन – सी संख्या दी गई श्रृंखला में प्रश्नवाचक चिह्न (?) का स्थान लेगी?
25, 26, 28, 32, 40, ?