55215820800 has 936 divisors, whose sum is σ = 235134908736. Its totient is φ = 12580945920.

The previous prime is 55215820787. The next prime is 55215820831. The reversal of 55215820800 is 802851255.

55215820800 is a `hidden beast` number, since 5 + 521 + 58 + 2 + 0 + 80 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 174182242 + ... + 174182558.

Almost surely, 2^55215820800 is an apocalyptic number.

55215820800 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55215820800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117567454368).

55215820800 is an abundant number, since it is smaller than the sum of its proper divisors (179919087936).

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

55215820800 is an equidigital number, since it uses as much as digits as its factorization.

55215820800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373 (or 334 counting only the distinct ones).

The product of its (nonzero) digits is 32000, while the sum is 36.

The spelling of 55215820800 in words is "fifty-five billion, two hundred fifteen million, eight hundred twenty thousand, eight hundred".