55597640 has 128 divisors (see below), whose sum is σ = 152409600. Its totient is φ = 17848320.

The previous prime is 55597639. The next prime is 55597651. The reversal of 55597640 is 4679555.

It is a Harshad number since it is a multiple of its sum of digits (41).

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, 332837 + ... + 333003.

It is an arithmetic number, because the mean of its divisors is an integer number (1190700).

Almost surely, 2^55597640 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 55597640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76204800).

55597640 is an abundant number, since it is smaller than the sum of its proper divisors (96811960).

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

55597640 is a wasteful number, since it uses less digits than its factorization.

55597640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255 (or 251 counting only the distinct ones).

The product of its (nonzero) digits is 189000, while the sum is 41.

The square root of 55597640 is about 7456.3825009183. The cubic root of 55597640 is about 381.6677391917.

The spelling of 55597640 in words is "fifty-five million, five hundred ninety-seven thousand, six hundred forty".