157906665 has 120 divisors (see below), whose sum is σ = 336849480. Its totient is φ = 70543872.

The previous prime is 157906643. The next prime is 157906667. The reversal of 157906665 is 566609751.

It can be written as a sum of positive squares in 4 ways, for example, as 30735936 + 127170729 = 5544^2 + 11277^2 .

It is not a de Polignac number, because 157906665 - 2⁵ = 157906633 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 157906665.

It is not an unprimeable number, because it can be changed into a prime (157906667) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1448631 + ... + 1448739.

It is an arithmetic number, because the mean of its divisors is an integer number (2807079).

Almost surely, 2^157906665 is an apocalyptic number.

157906665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

157906665 is an abundant number, since it is smaller than the sum of its proper divisors (178942815).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

157906665 is a wasteful number, since it uses less digits than its factorization.

157906665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 45.

The square root of 157906665 is about 12566.0918745647. The cubic root of 157906665 is about 540.5055450822.

The spelling of 157906665 in words is "one hundred fifty-seven million, nine hundred six thousand, six hundred sixty-five".