55684221 has 4 divisors (see below), whose sum is σ = 74245632. Its totient is φ = 37122812.

The previous prime is 55684207. The next prime is 55684243. The reversal of 55684221 is 12248655.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55684221 - 2⁹ = 55683709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55684261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9280701 + ... + 9280706.

It is an arithmetic number, because the mean of its divisors is an integer number (18561408).

Almost surely, 2^55684221 is an apocalyptic number.

It is an amenable number.

55684221 is a deficient number, since it is larger than the sum of its proper divisors (18561411).

55684221 is a wasteful number, since it uses less digits than its factorization.

55684221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18561410.

The product of its digits is 19200, while the sum is 33.

The square root of 55684221 is about 7462.1860737990. The cubic root of 55684221 is about 381.8657574040.

The spelling of 55684221 in words is "fifty-five million, six hundred eighty-four thousand, two hundred twenty-one".