55400728 has 16 divisors (see below), whose sum is σ = 104107680. Its totient is φ = 27638688.

The previous prime is 55400699. The next prime is 55400743. The reversal of 55400728 is 82700455.

It is a self number, because there is not a number n which added to its sum of digits gives 55400728.

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, 3775 + ... + 11182.

It is an arithmetic number, because the mean of its divisors is an integer number (6506730).

Almost surely, 2^55400728 is an apocalyptic number.

It is an amenable number.

55400728 is a deficient number, since it is larger than the sum of its proper divisors (48706952).

55400728 is a wasteful number, since it uses less digits than its factorization.

55400728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15426 (or 15422 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 55400728 is about 7443.1665304493. The cubic root of 55400728 is about 381.2166177705.

The spelling of 55400728 in words is "fifty-five million, four hundred thousand, seven hundred twenty-eight".