631211988 has 36 divisors (see below), whose sum is σ = 1618897280. Its totient is φ = 191275920.

The previous prime is 631211899. The next prime is 631212013. The reversal of 631211988 is 889112136.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 215908 + ... + 218811.

Almost surely, 2^631211988 is an apocalyptic number.

It is an amenable number.

631211988 is an abundant number, since it is smaller than the sum of its proper divisors (987685292).

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

631211988 is a wasteful number, since it uses less digits than its factorization.

631211988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434748 (or 434735 counting only the distinct ones).

The product of its digits is 20736, while the sum is 39.

The square root of 631211988 is about 25123.9325743403. The cubic root of 631211988 is about 857.8112668374.

The spelling of 631211988 in words is "six hundred thirty-one million, two hundred eleven thousand, nine hundred eighty-eight".