157991474 has 8 divisors (see below), whose sum is σ = 237040668. Its totient is φ = 78977920.

The previous prime is 157991447. The next prime is 157991539. The reversal of 157991474 is 474199751.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 142444225 + 15547249 = 11935^2 + 3943^2 .

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

It is a super-2 number, since 2×157991474² = 49922611713385352, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11834 + ... + 21354.

Almost surely, 2^157991474 is an apocalyptic number.

157991474 is a deficient number, since it is larger than the sum of its proper divisors (79049194).

157991474 is an equidigital number, since it uses as much as digits as its factorization.

157991474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17820.

The product of its digits is 317520, while the sum is 47.

The square root of 157991474 is about 12569.4659393309. The cubic root of 157991474 is about 540.6022932270.

The spelling of 157991474 in words is "one hundred fifty-seven million, nine hundred ninety-one thousand, four hundred seventy-four".