19957131 has 8 divisors (see below), whose sum is σ = 29566160. Its totient is φ = 13304736.

The previous prime is 19957129. The next prime is 19957139. The reversal of 19957131 is 13175991.

It is not a de Polignac number, because 19957131 - 2¹ = 19957129 is a prime.

It is a super-2 number, since 2×19957131² = 796574155502322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19957139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 369550 + ... + 369603.

It is an arithmetic number, because the mean of its divisors is an integer number (3695770).

Almost surely, 2^19957131 is an apocalyptic number.

19957131 is a deficient number, since it is larger than the sum of its proper divisors (9609029).

19957131 is an equidigital number, since it uses as much as digits as its factorization.

19957131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739162 (or 739156 counting only the distinct ones).

The product of its digits is 8505, while the sum is 36.

The square root of 19957131 is about 4467.3404840016. The cubic root of 19957131 is about 271.2476823122.

The spelling of 19957131 in words is "nineteen million, nine hundred fifty-seven thousand, one hundred thirty-one".