157991911 has 32 divisors (see below), whose sum is σ = 203212800. Its totient is φ = 119280480.

The previous prime is 157991881. The next prime is 157991959. The reversal of 157991911 is 119199751.

It is not a de Polignac number, because 157991911 - 2⁵ = 157991879 is a prime.

It is a super-2 number, since 2×157991911² = 49922887882863842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (157991411) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 376860 + ... + 377278.

It is an arithmetic number, because the mean of its divisors is an integer number (6350400).

Almost surely, 2^157991911 is an apocalyptic number.

157991911 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

157991911 is a deficient number, since it is larger than the sum of its proper divisors (45220889).

157991911 is a wasteful number, since it uses less digits than its factorization.

157991911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 579.

The product of its digits is 25515, while the sum is 43.

The square root of 157991911 is about 12569.4833227146. The cubic root of 157991911 is about 540.6027916568.

The spelling of 157991911 in words is "one hundred fifty-seven million, nine hundred ninety-one thousand, nine hundred eleven".