55772218 has 24 divisors (see below), whose sum is σ = 87645564. Its totient is φ = 26607360.

The previous prime is 55772203. The next prime is 55772237. The reversal of 55772218 is 81227755.

It can be written as a sum of positive squares in 6 ways, for example, as 16129 + 55756089 = 127^2 + 7467^2 .

It is a super-2 number, since 2×55772218² = 6221080601279048, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 178030 + ... + 178342.

Almost surely, 2^55772218 is an apocalyptic number.

55772218 is a deficient number, since it is larger than the sum of its proper divisors (31873346).

55772218 is a wasteful number, since it uses less digits than its factorization.

55772218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450 (or 409 counting only the distinct ones).

The product of its digits is 39200, while the sum is 37.

The square root of 55772218 is about 7468.0799406541. The cubic root of 55772218 is about 382.0668039193.

The spelling of 55772218 in words is "fifty-five million, seven hundred seventy-two thousand, two hundred eighteen".