55531980 has 240 divisors, whose sum is σ = 204906240. Its totient is φ = 12327552.

The previous prime is 55531937. The next prime is 55532017. The reversal of 55531980 is 8913555.

It is a happy number.

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 79 ways as a sum of consecutive naturals, for example, 669019 + ... + 669101.

It is an arithmetic number, because the mean of its divisors is an integer number (853776).

Almost surely, 2^55531980 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 55531980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102453120).

55531980 is an abundant number, since it is smaller than the sum of its proper divisors (149374260).

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

55531980 is a wasteful number, since it uses less digits than its factorization.

55531980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The square root of 55531980 is about 7451.9782608379. The cubic root of 55531980 is about 381.5174319993.

The spelling of 55531980 in words is "fifty-five million, five hundred thirty-one thousand, nine hundred eighty".