1987131840 has 56 divisors (see below), whose sum is σ = 6309146640. Its totient is φ = 529901568.

The previous prime is 1987131829. The next prime is 1987131863. The reversal of 1987131840 is 481317891.

It is a junction number, because it is equal to n+sod(n) for n = 1987131792 and 1987131801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1034005 + ... + 1035924.

Almost surely, 2^1987131840 is an apocalyptic number.

1987131840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1987131840 is an abundant number, since it is smaller than the sum of its proper divisors (4322014800).

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

1987131840 is a wasteful number, since it uses less digits than its factorization.

1987131840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2069949 (or 2069939 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 42.

The square root of 1987131840 is about 44577.2569815596. The cubic root of 1987131840 is about 1257.2130895434.

The spelling of 1987131840 in words is "one billion, nine hundred eighty-seven million, one hundred thirty-one thousand, eight hundred forty".