813131937 has 6 divisors (see below), whose sum is σ = 1174523922. Its totient is φ = 542087952.

The previous prime is 813131909. The next prime is 813131939. The reversal of 813131937 is 739131318.

It can be written as a sum of positive squares in only one way, i.e., 718186401 + 94945536 = 26799^2 + 9744^2 .

It is not a de Polignac number, because 813131937 - 2⁶ = 813131873 is a prime.

It is a super-2 number, since 2×813131937² = 1322367093938743938, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (813131939) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45173988 + ... + 45174005.

It is an arithmetic number, because the mean of its divisors is an integer number (195753987).

Almost surely, 2^813131937 is an apocalyptic number.

It is an amenable number.

813131937 is a deficient number, since it is larger than the sum of its proper divisors (361391985).

813131937 is a wasteful number, since it uses less digits than its factorization.

813131937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90347999 (or 90347996 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 813131937 is about 28515.4683812137. The cubic root of 813131937 is about 933.3696456819.

The spelling of 813131937 in words is "eight hundred thirteen million, one hundred thirty-one thousand, nine hundred thirty-seven".