1987992 has 24 divisors (see below), whose sum is σ = 5384340. Its totient is φ = 662640.

The previous prime is 1987991. The next prime is 1988011. The reversal of 1987992 is 2997891.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×1987992² = 7904224384128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13734 + ... + 13877.

2^1987992 is an apocalyptic number.

1987992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1987992 is an abundant number, since it is smaller than the sum of its proper divisors (3396348).

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

1987992 is a wasteful number, since it uses less digits than its factorization.

1987992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27623 (or 27616 counting only the distinct ones).

The product of its digits is 81648, while the sum is 45.

The square root of 1987992 is about 1409.9617016075. The cubic root of 1987992 is about 125.7394464594.

The spelling of 1987992 in words is "one million, nine hundred eighty-seven thousand, nine hundred ninety-two".