636679697 has 2 divisors, whose sum is σ = 636679698. Its totient is φ = 636679696.

The previous prime is 636679663. The next prime is 636679709. The reversal of 636679697 is 796976636.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 427703761 + 208975936 = 20681^2 + 14456^2 .

It is a cyclic number.

It is not a de Polignac number, because 636679697 - 2⁸ = 636679441 is a prime.

It is a super-2 number, since 2×636679697² = 810722073144023618, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (636679097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318339848 + 318339849.

It is an arithmetic number, because the mean of its divisors is an integer number (318339849).

Almost surely, 2^636679697 is an apocalyptic number.

It is an amenable number.

636679697 is a deficient number, since it is larger than the sum of its proper divisors (1).

636679697 is an equidigital number, since it uses as much as digits as its factorization.

636679697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15431472, while the sum is 59.

The square root of 636679697 is about 25232.5126969155. The cubic root of 636679697 is about 860.2810047105.

The spelling of 636679697 in words is "six hundred thirty-six million, six hundred seventy-nine thousand, six hundred ninety-seven".