55691280 has 320 divisors, whose sum is σ = 214272000. Its totient is φ = 13229568.

The previous prime is 55691267. The next prime is 55691291. The reversal of 55691280 is 8219655.

It is a happy number.

55691280 is a `hidden beast` number, since 5 + 569 + 12 + 80 = 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 63 ways as a sum of consecutive naturals, for example, 943891 + ... + 943949.

It is an arithmetic number, because the mean of its divisors is an integer number (669600).

Almost surely, 2^55691280 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 55691280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107136000).

55691280 is an abundant number, since it is smaller than the sum of its proper divisors (158580720).

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

55691280 is a wasteful number, since it uses less digits than its factorization.

55691280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 55691280 is about 7462.6590435313. The cubic root of 55691280 is about 381.8818928935.

The spelling of 55691280 in words is "fifty-five million, six hundred ninety-one thousand, two hundred eighty".