55399680 has 288 divisors, whose sum is σ = 225657600. Its totient is φ = 12607488.

The previous prime is 55399679. The next prime is 55399727. The reversal of 55399680 is 8699355.

55399680 is a `hidden beast` number, since 553 + 9 + 96 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 241806 + ... + 242034.

Almost surely, 2^55399680 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55399680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112828800).

55399680 is an abundant number, since it is smaller than the sum of its proper divisors (170257920).

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

55399680 is a wasteful number, since it uses less digits than its factorization.

55399680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The square root of 55399680 is about 7443.0961299717. The cubic root of 55399680 is about 381.2142139661.

The spelling of 55399680 in words is "fifty-five million, three hundred ninety-nine thousand, six hundred eighty".