1981977432 has 16 divisors (see below), whose sum is σ = 4954943640. Its totient is φ = 660659136.

The previous prime is 1981977407. The next prime is 1981977443. The reversal of 1981977432 is 2347791891.

It is a congruent number.

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, 41291173 + ... + 41291220.

Almost surely, 2^1981977432 is an apocalyptic number.

1981977432 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1981977432 is an abundant number, since it is smaller than the sum of its proper divisors (2972966208).

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

1981977432 is a wasteful number, since it uses less digits than its factorization.

1981977432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82582402 (or 82582398 counting only the distinct ones).

The product of its digits is 762048, while the sum is 51.

The square root of 1981977432 is about 44519.4051173193. The cubic root of 1981977432 is about 1256.1251227668.

The spelling of 1981977432 in words is "one billion, nine hundred eighty-one million, nine hundred seventy-seven thousand, four hundred thirty-two".