631873881 has 12 divisors (see below), whose sum is σ = 915590052. Its totient is φ = 419918496.

The previous prime is 631873873. The next prime is 631873889. The reversal of 631873881 is 188378136.

631873881 is a `hidden beast` number, since 631 + 8 + 7 + 3 + 8 + 8 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (631873873) and next prime (631873889).

It can be written as a sum of positive squares in 2 ways, for example, as 16040025 + 615833856 = 4005^2 + 24816^2 .

It is not a de Polignac number, because 631873881 - 2³ = 631873873 is a prime.

It is a super-2 number, since 2×631873881² = 798529202980004322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (631873889) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 107886 + ... + 113591.

It is an arithmetic number, because the mean of its divisors is an integer number (76299171).

Almost surely, 2^631873881 is an apocalyptic number.

It is an amenable number.

631873881 is a deficient number, since it is larger than the sum of its proper divisors (283716171).

631873881 is a wasteful number, since it uses less digits than its factorization.

631873881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221800 (or 221797 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 631873881 is about 25137.1016825727. The cubic root of 631873881 is about 858.1109975883.

The spelling of 631873881 in words is "six hundred thirty-one million, eight hundred seventy-three thousand, eight hundred eighty-one".