165215057 has 4 divisors (see below), whose sum is σ = 188817216. Its totient is φ = 141612900.

The previous prime is 165215053. The next prime is 165215077. The reversal of 165215057 is 750512561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 750512561 = 79 ⋅9500159.

It is a cyclic number.

It is not a de Polignac number, because 165215057 - 2² = 165215053 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165215053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11801069 + ... + 11801082.

It is an arithmetic number, because the mean of its divisors is an integer number (47204304).

Almost surely, 2^165215057 is an apocalyptic number.

It is an amenable number.

165215057 is a deficient number, since it is larger than the sum of its proper divisors (23602159).

165215057 is an equidigital number, since it uses as much as digits as its factorization.

165215057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23602158.

The product of its (nonzero) digits is 10500, while the sum is 32.

The square root of 165215057 is about 12853.6009351465. The cubic root of 165215057 is about 548.7188439199.

The spelling of 165215057 in words is "one hundred sixty-five million, two hundred fifteen thousand, fifty-seven".