1987117812 has 48 divisors (see below), whose sum is σ = 5422939200. Its totient is φ = 627510240.

The previous prime is 1987117807. The next prime is 1987117823. The reversal of 1987117812 is 2187117891.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 482139 + ... + 486242.

It is an arithmetic number, because the mean of its divisors is an integer number (112977900).

Almost surely, 2^1987117812 is an apocalyptic number.

1987117812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1987117812 is an abundant number, since it is smaller than the sum of its proper divisors (3435821388).

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

1987117812 is a wasteful number, since it uses less digits than its factorization.

1987117812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 968413 (or 968405 counting only the distinct ones).

The product of its digits is 56448, while the sum is 45.

The square root of 1987117812 is about 44577.0996364725. The cubic root of 1987117812 is about 1257.2101311377.

The spelling of 1987117812 in words is "one billion, nine hundred eighty-seven million, one hundred seventeen thousand, eight hundred twelve".