157931491 has 4 divisors (see below), whose sum is σ = 158020984. Its totient is φ = 157842000.

The previous prime is 157931489. The next prime is 157931497. The reversal of 157931491 is 194139751.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 157931491 - 2¹ = 157931489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157931497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42045 + ... + 45646.

It is an arithmetic number, because the mean of its divisors is an integer number (39505246).

Almost surely, 2^157931491 is an apocalyptic number.

157931491 is a deficient number, since it is larger than the sum of its proper divisors (89493).

157931491 is an equidigital number, since it uses as much as digits as its factorization.

157931491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89492.

The product of its digits is 34020, while the sum is 40.

The square root of 157931491 is about 12567.0796528072. The cubic root of 157931491 is about 540.5338695939.

The spelling of 157931491 in words is "one hundred fifty-seven million, nine hundred thirty-one thousand, four hundred ninety-one".