55987780 has 24 divisors (see below), whose sum is σ = 118359360. Its totient is φ = 22245600.

The previous prime is 55987759. The next prime is 55987781. The reversal of 55987780 is 8778955.

It is not an unprimeable number, because it can be changed into a prime (55987781) 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, 6250 + ... + 12289.

It is an arithmetic number, because the mean of its divisors is an integer number (4931640).

Almost surely, 2^55987780 is an apocalyptic number.

It is an amenable number.

55987780 is an abundant number, since it is smaller than the sum of its proper divisors (62371580).

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

55987780 is a wasteful number, since it uses less digits than its factorization.

55987780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18699 (or 18697 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 49.

The square root of 55987780 is about 7482.4982459069. The cubic root of 55987780 is about 382.5584059359.

The spelling of 55987780 in words is "fifty-five million, nine hundred eighty-seven thousand, seven hundred eighty".