68315531 has 2 divisors, whose sum is σ = 68315532. Its totient is φ = 68315530.

The previous prime is 68315501. The next prime is 68315549. The reversal of 68315531 is 13551386.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 68315531 - 2²² = 64121227 is a prime.

It is a super-2 number, since 2×68315531² = 9334023551623922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (68315501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34157765 + 34157766.

It is an arithmetic number, because the mean of its divisors is an integer number (34157766).

Almost surely, 2^68315531 is an apocalyptic number.

68315531 is a deficient number, since it is larger than the sum of its proper divisors (1).

68315531 is an equidigital number, since it uses as much as digits as its factorization.

68315531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 32.

The square root of 68315531 is about 8265.3209859025. The cubic root of 68315531 is about 408.7958542267.

The spelling of 68315531 in words is "sixty-eight million, three hundred fifteen thousand, five hundred thirty-one".