55220155 has 4 divisors (see below), whose sum is σ = 66264192. Its totient is φ = 44176120.

The previous prime is 55220141. The next prime is 55220167. The reversal of 55220155 is 55102255.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a de Polignac number, because none of the positive numbers 2^k-55220155 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5522011 + ... + 5522020.

It is an arithmetic number, because the mean of its divisors is an integer number (16566048).

Almost surely, 2^55220155 is an apocalyptic number.

55220155 is a deficient number, since it is larger than the sum of its proper divisors (11044037).

55220155 is a wasteful number, since it uses less digits than its factorization.

55220155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11044036.

The product of its (nonzero) digits is 2500, while the sum is 25.

The square root of 55220155 is about 7431.0265105166. The cubic root of 55220155 is about 380.8019881194.

The spelling of 55220155 in words is "fifty-five million, two hundred twenty thousand, one hundred fifty-five".