55722222 has 48 divisors (see below), whose sum is σ = 127939920. Its totient is φ = 17963856.

The previous prime is 55722203. The next prime is 55722223. The reversal of 55722222 is 22222755.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55722223) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 333583 + ... + 333749.

It is an arithmetic number, because the mean of its divisors is an integer number (2665415).

Almost surely, 2^55722222 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55722222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63969960).

55722222 is an abundant number, since it is smaller than the sum of its proper divisors (72217698).

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

55722222 is a wasteful number, since it uses less digits than its factorization.

55722222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 209 counting only the distinct ones).

The product of its digits is 5600, while the sum is 27.

The square root of 55722222 is about 7464.7318773014. The cubic root of 55722222 is about 381.9526041542.

Adding to 55722222 its reverse (22222755), we get a palindrome (77944977).

The spelling of 55722222 in words is "fifty-five million, seven hundred twenty-two thousand, two hundred twenty-two".