55075221 has 16 divisors (see below), whose sum is σ = 82603520. Its totient is φ = 36715356.

The previous prime is 55075219. The next prime is 55075249. The reversal of 55075221 is 12257055.

It is a happy number.

It is not a de Polignac number, because 55075221 - 2¹ = 55075219 is a prime.

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

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55075021) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 10405 + ... + 14778.

It is an arithmetic number, because the mean of its divisors is an integer number (5162720).

Almost surely, 2^55075221 is an apocalyptic number.

It is an amenable number.

55075221 is a deficient number, since it is larger than the sum of its proper divisors (27528299).

55075221 is an frugal number, since it uses more digits than its factorization.

55075221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25204 (or 25186 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 55075221 is about 7421.2681530854. The cubic root of 55075221 is about 380.4685379396.

The spelling of 55075221 in words is "fifty-five million, seventy-five thousand, two hundred twenty-one".