158856921 has 24 divisors (see below), whose sum is σ = 235531296. Its totient is φ = 103118400.

The previous prime is 158856917. The next prime is 158856923. The reversal of 158856921 is 129658851.

It is a happy number.

158856921 is a `hidden beast` number, since 1 + 5 + 88 + 569 + 2 + 1 = 666.

It is not a de Polignac number, because 158856921 - 2² = 158856917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (158856923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 232246 + ... + 232928.

It is an arithmetic number, because the mean of its divisors is an integer number (9813804).

Almost surely, 2^158856921 is an apocalyptic number.

It is an amenable number.

158856921 is a deficient number, since it is larger than the sum of its proper divisors (76674375).

158856921 is a wasteful number, since it uses less digits than its factorization.

158856921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1333 (or 1330 counting only the distinct ones).

The product of its digits is 172800, while the sum is 45.

The square root of 158856921 is about 12603.8454846130. The cubic root of 158856921 is about 541.5876015353.

The spelling of 158856921 in words is "one hundred fifty-eight million, eight hundred fifty-six thousand, nine hundred twenty-one".