55724640 has 96 divisors (see below), whose sum is σ = 185885280. Its totient is φ = 13983744.

The previous prime is 55724633. The next prime is 55724693. The reversal of 55724640 is 4642755.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4746 + ... + 11574.

It is an arithmetic number, because the mean of its divisors is an integer number (1936305).

Almost surely, 2^55724640 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 55724640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92942640).

55724640 is an abundant number, since it is smaller than the sum of its proper divisors (130160640).

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

55724640 is a wasteful number, since it uses less digits than its factorization.

55724640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6864 (or 6856 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 33.

The square root of 55724640 is about 7464.8938371554. The cubic root of 55724640 is about 381.9581288683.

The spelling of 55724640 in words is "fifty-five million, seven hundred twenty-four thousand, six hundred forty".