55249921 has 4 divisors (see below), whose sum is σ = 55786432. Its totient is φ = 54713412.

The previous prime is 55249913. The next prime is 55249927. The reversal of 55249921 is 12994255.

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 55249921 - 2³ = 55249913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55249927) 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, 268101 + ... + 268306.

It is an arithmetic number, because the mean of its divisors is an integer number (13946608).

Almost surely, 2^55249921 is an apocalyptic number.

It is an amenable number.

55249921 is a deficient number, since it is larger than the sum of its proper divisors (536511).

55249921 is a wasteful number, since it uses less digits than its factorization.

55249921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536510.

The product of its digits is 32400, while the sum is 37.

The square root of 55249921 is about 7433.0290595423. The cubic root of 55249921 is about 380.8703986235.

The spelling of 55249921 in words is "fifty-five million, two hundred forty-nine thousand, nine hundred twenty-one".