1631387980 has 12 divisors (see below), whose sum is σ = 3425914800. Its totient is φ = 652555184.

The previous prime is 1631387977. The next prime is 1631387993. The reversal of 1631387980 is 897831361.

It is a super-2 number, since 2×1631387980² = 5322853482576960800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1631387980.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40784680 + ... + 40784719.

It is an arithmetic number, because the mean of its divisors is an integer number (285492900).

Almost surely, 2^1631387980 is an apocalyptic number.

1631387980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1631387980 is an abundant number, since it is smaller than the sum of its proper divisors (1794526820).

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

1631387980 is a wasteful number, since it uses less digits than its factorization.

1631387980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81569408 (or 81569406 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 1631387980 is about 40390.4441669066. Note that the first 3 decimals coincide. The cubic root of 1631387980 is about 1177.2058710331.

The spelling of 1631387980 in words is "one billion, six hundred thirty-one million, three hundred eighty-seven thousand, nine hundred eighty".