55920640 has 96 divisors (see below), whose sum is σ = 138378240. Its totient is φ = 21676032.

The previous prime is 55920607. The next prime is 55920691. The reversal of 55920640 is 4602955.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 440257 + ... + 440383.

It is an arithmetic number, because the mean of its divisors is an integer number (1441440).

Almost surely, 2^55920640 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 55920640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69189120).

55920640 is an abundant number, since it is smaller than the sum of its proper divisors (82457600).

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

55920640 is a wasteful number, since it uses less digits than its factorization.

55920640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 55920640 is about 7478.0104305891. The cubic root of 55920640 is about 382.4054246647.

The spelling of 55920640 in words is "fifty-five million, nine hundred twenty thousand, six hundred forty".