55222780 has 24 divisors (see below), whose sum is σ = 119710080. Its totient is φ = 21376320.

The previous prime is 55222733. The next prime is 55222781. The reversal of 55222780 is 8722255.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55222781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43915 + ... + 45154.

It is an arithmetic number, because the mean of its divisors is an integer number (4987920).

Almost surely, 2^55222780 is an apocalyptic number.

It is an amenable number.

55222780 is an abundant number, since it is smaller than the sum of its proper divisors (64487300).

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

55222780 is a wasteful number, since it uses less digits than its factorization.

55222780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89109 (or 89107 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 55222780 is about 7431.2031327370. The cubic root of 55222780 is about 380.8080220840.

It can be divided in two parts, 552 and 22780, that added together give a palindrome (23332).

The spelling of 55222780 in words is "fifty-five million, two hundred twenty-two thousand, seven hundred eighty".