158857021 has 8 divisors (see below), whose sum is σ = 170244864. Its totient is φ = 147842640.

The previous prime is 158857009. The next prime is 158857031. The reversal of 158857021 is 120758851.

It is the 5146-th star number.

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

It is a cyclic number.

It is not a de Polignac number, because 158857021 - 2¹⁷ = 158725949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (158857031) 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, 92485 + ... + 94186.

It is an arithmetic number, because the mean of its divisors is an integer number (21280608).

Almost surely, 2^158857021 is an apocalyptic number.

It is an amenable number.

158857021 is a deficient number, since it is larger than the sum of its proper divisors (11387843).

158857021 is a wasteful number, since it uses less digits than its factorization.

158857021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186731.

The product of its (nonzero) digits is 22400, while the sum is 37.

The square root of 158857021 is about 12603.8494516556. The cubic root of 158857021 is about 541.5877151779.

The spelling of 158857021 in words is "one hundred fifty-eight million, eight hundred fifty-seven thousand, twenty-one".