55219421 has 4 divisors (see below), whose sum is σ = 55234332. Its totient is φ = 55204512.

The previous prime is 55219403. The next prime is 55219447. The reversal of 55219421 is 12491255.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 16605625 + 38613796 = 4075^2 + 6214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55219421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55219321) 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, 2831 + ... + 10883.

It is an arithmetic number, because the mean of its divisors is an integer number (13808583).

Almost surely, 2^55219421 is an apocalyptic number.

It is an amenable number.

55219421 is a deficient number, since it is larger than the sum of its proper divisors (14911).

55219421 is an equidigital number, since it uses as much as digits as its factorization.

55219421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14910.

The product of its digits is 3600, while the sum is 29.

The square root of 55219421 is about 7430.9771228285. The cubic root of 55219421 is about 380.8003008738.

The spelling of 55219421 in words is "fifty-five million, two hundred nineteen thousand, four hundred twenty-one".