55991788 has 6 divisors (see below), whose sum is σ = 97985636. Its totient is φ = 27995892.

The previous prime is 55991783. The next prime is 55991791. The reversal of 55991788 is 88719955.

It is not an unprimeable number, because it can be changed into a prime (55991783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6998970 + ... + 6998977.

Almost surely, 2^55991788 is an apocalyptic number.

It is an amenable number.

55991788 is a deficient number, since it is larger than the sum of its proper divisors (41993848).

55991788 is a wasteful number, since it uses less digits than its factorization.

55991788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13997951 (or 13997949 counting only the distinct ones).

The product of its digits is 907200, while the sum is 52.

The square root of 55991788 is about 7482.7660661015. The cubic root of 55991788 is about 382.5675344607.

The spelling of 55991788 in words is "fifty-five million, nine hundred ninety-one thousand, seven hundred eighty-eight".