55221718 has 8 divisors (see below), whose sum is σ = 84759048. Its totient is φ = 26968704.

The previous prime is 55221709. The next prime is 55221721. The reversal of 55221718 is 81712255.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 55221718.

It is a congruent 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, 320971 + ... + 321142.

It is an arithmetic number, because the mean of its divisors is an integer number (10594881).

Almost surely, 2^55221718 is an apocalyptic number.

55221718 is a deficient number, since it is larger than the sum of its proper divisors (29537330).

55221718 is a wasteful number, since it uses less digits than its factorization.

55221718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642158.

The product of its digits is 5600, while the sum is 31.

The square root of 55221718 is about 7431.1316769386. The cubic root of 55221718 is about 380.8055809374.

The spelling of 55221718 in words is "fifty-five million, two hundred twenty-one thousand, seven hundred eighteen".