156638961 has 16 divisors (see below), whose sum is σ = 233732800. Its totient is φ = 103672224.

The previous prime is 156638959. The next prime is 156638987. The reversal of 156638961 is 169836651.

156638961 is a `hidden beast` number, since 1 + 5 + 6 + 638 + 9 + 6 + 1 = 666.

It is not a de Polignac number, because 156638961 - 2¹ = 156638959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (156638941) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17116 + ... + 24621.

It is an arithmetic number, because the mean of its divisors is an integer number (14608300).

Almost surely, 2^156638961 is an apocalyptic number.

It is an amenable number.

156638961 is a deficient number, since it is larger than the sum of its proper divisors (77093839).

156638961 is a wasteful number, since it uses less digits than its factorization.

156638961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41885 (or 41879 counting only the distinct ones).

The product of its digits is 233280, while the sum is 45.

The square root of 156638961 is about 12515.5487694308. The cubic root of 156638961 is about 539.0552307375.

The spelling of 156638961 in words is "one hundred fifty-six million, six hundred thirty-eight thousand, nine hundred sixty-one".