68513931 has 20 divisors (see below), whose sum is σ = 103758952. Its totient is φ = 45046368.

The previous prime is 68513923. The next prime is 68513933. The reversal of 68513931 is 13931586.

It is a happy number.

It is not a de Polignac number, because 68513931 - 2³ = 68513923 is a prime.

It is a super-2 number, since 2×68513931² = 9388317482145522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68513933) 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 in 19 ways as a sum of consecutive naturals, for example, 120 + ... + 11706.

Almost surely, 2^68513931 is an apocalyptic number.

68513931 is a deficient number, since it is larger than the sum of its proper divisors (35245021).

68513931 is a wasteful number, since it uses less digits than its factorization.

68513931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11672 (or 11663 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 68513931 is about 8277.3142383263. The cubic root of 68513931 is about 409.1912094671.

The spelling of 68513931 in words is "sixty-eight million, five hundred thirteen thousand, nine hundred thirty-one".