55397620 has 48 divisors (see below), whose sum is σ = 120960000. Its totient is φ = 21288960.

The previous prime is 55397609. The next prime is 55397647. The reversal of 55397620 is 2679355.

It is a self number, because there is not a number n which added to its sum of digits gives 55397620.

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, 123156 + ... + 123604.

It is an arithmetic number, because the mean of its divisors is an integer number (2520000).

Almost surely, 2^55397620 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 55397620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60480000).

55397620 is an abundant number, since it is smaller than the sum of its proper divisors (65562380).

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

55397620 is a wasteful number, since it uses less digits than its factorization.

55397620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688 (or 686 counting only the distinct ones).

The product of its (nonzero) digits is 56700, while the sum is 37.

The square root of 55397620 is about 7442.9577454128. The cubic root of 55397620 is about 381.2094888425.

The spelling of 55397620 in words is "fifty-five million, three hundred ninety-seven thousand, six hundred twenty".