631977138 has 48 divisors (see below), whose sum is σ = 1478917440. Its totient is φ = 193887072.

The previous prime is 631977127. The next prime is 631977173. The reversal of 631977138 is 831779136.

631977138 is a `hidden beast` number, since 631 + 9 + 7 + 7 + 1 + 3 + 8 = 666.

631977138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 631977093 and 631977102.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80245 + ... + 87767.

It is an arithmetic number, because the mean of its divisors is an integer number (30810780).

Almost surely, 2^631977138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 631977138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (739458720).

631977138 is an abundant number, since it is smaller than the sum of its proper divisors (846940302).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

631977138 is a wasteful number, since it uses less digits than its factorization.

631977138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7903 (or 7900 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 631977138 is about 25139.1554750751. The cubic root of 631977138 is about 858.1577374752.

The spelling of 631977138 in words is "six hundred thirty-one million, nine hundred seventy-seven thousand, one hundred thirty-eight".