68657531 has 2 divisors, whose sum is σ = 68657532. Its totient is φ = 68657530.

The previous prime is 68657527. The next prime is 68657539. The reversal of 68657531 is 13575686.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 68657531 - 2² = 68657527 is a prime.

It is a super-2 number, since 2×68657531² = 9427713126031922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (68657539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34328765 + 34328766.

It is an arithmetic number, because the mean of its divisors is an integer number (34328766).

Almost surely, 2^68657531 is an apocalyptic number.

68657531 is a deficient number, since it is larger than the sum of its proper divisors (1).

68657531 is an equidigital number, since it uses as much as digits as its factorization.

68657531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 151200, while the sum is 41.

The square root of 68657531 is about 8285.9840091567. The cubic root of 68657531 is about 409.4768878806.

The spelling of 68657531 in words is "sixty-eight million, six hundred fifty-seven thousand, five hundred thirty-one".