1980855564 has 24 divisors (see below), whose sum is σ = 4865259840. Its totient is φ = 625533264.

The previous prime is 1980855563. The next prime is 1980855581. The reversal of 1980855564 is 4655580891.

It is not an unprimeable number, because it can be changed into a prime (1980855563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4343754 + ... + 4344209.

It is an arithmetic number, because the mean of its divisors is an integer number (202719160).

Almost surely, 2^1980855564 is an apocalyptic number.

It is an amenable number.

1980855564 is an abundant number, since it is smaller than the sum of its proper divisors (2884404276).

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

1980855564 is a wasteful number, since it uses less digits than its factorization.

1980855564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8687989 (or 8687987 counting only the distinct ones).

The product of its (nonzero) digits is 1728000, while the sum is 51.

The square root of 1980855564 is about 44506.8035697914. The cubic root of 1980855564 is about 1255.8880745666. Note that the first 3 decimals are identical.

The spelling of 1980855564 in words is "one billion, nine hundred eighty million, eight hundred fifty-five thousand, five hundred sixty-four".