168128931 has 8 divisors (see below), whose sum is σ = 225299200. Its totient is φ = 111522312.

The previous prime is 168128899. The next prime is 168128941. The reversal of 168128931 is 139821861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 168128931 - 2⁵ = 168128899 is a prime.

It is a super-2 number, since 2×168128931² = 56534674878405522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 168128931.

It is not an unprimeable number, because it can be changed into a prime (168128941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 140215 + ... + 141408.

It is an arithmetic number, because the mean of its divisors is an integer number (28162400).

Almost surely, 2^168128931 is an apocalyptic number.

168128931 is a deficient number, since it is larger than the sum of its proper divisors (57170269).

168128931 is a wasteful number, since it uses less digits than its factorization.

168128931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281825.

The product of its digits is 20736, while the sum is 39.

The square root of 168128931 is about 12966.4540642382. The cubic root of 168128931 is about 551.9259542823.

The spelling of 168128931 in words is "one hundred sixty-eight million, one hundred twenty-eight thousand, nine hundred thirty-one".