55721106 has 48 divisors (see below), whose sum is σ = 139299264. Its totient is φ = 15767712.

The previous prime is 55721063. The next prime is 55721117. The reversal of 55721106 is 60112755.

55721106 is a `hidden beast` number, since 557 + 2 + 1 + 106 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 55721106.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11416 + ... + 15548.

It is an arithmetic number, because the mean of its divisors is an integer number (2902068).

Almost surely, 2^55721106 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55721106, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69649632).

55721106 is an abundant number, since it is smaller than the sum of its proper divisors (83578158).

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

55721106 is a wasteful number, since it uses less digits than its factorization.

55721106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4255 (or 4252 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 27.

The square root of 55721106 is about 7464.6571254144. The cubic root of 55721106 is about 381.9500542322.

The spelling of 55721106 in words is "fifty-five million, seven hundred twenty-one thousand, one hundred six".