55444421 has 4 divisors (see below), whose sum is σ = 57855072. Its totient is φ = 53033772.

The previous prime is 55444387. The next prime is 55444427. The reversal of 55444421 is 12444455.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12444455 = 5 ⋅2488891.

It is a cyclic number.

It is not a de Polignac number, because 55444421 - 2²² = 51250117 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55444427) 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, 1205291 + ... + 1205336.

It is an arithmetic number, because the mean of its divisors is an integer number (14463768).

Almost surely, 2^55444421 is an apocalyptic number.

It is an amenable number.

55444421 is a deficient number, since it is larger than the sum of its proper divisors (2410651).

55444421 is a wasteful number, since it uses less digits than its factorization.

55444421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2410650.

The product of its digits is 12800, while the sum is 29.

The square root of 55444421 is about 7446.1010602865. The cubic root of 55444421 is about 381.3168097196.

Adding to 55444421 its reverse (12444455), we get a palindrome (67888876).

The spelling of 55444421 in words is "fifty-five million, four hundred forty-four thousand, four hundred twenty-one".