55242621 has 32 divisors (see below), whose sum is σ = 95827200. Its totient is φ = 30792960.

The previous prime is 55242613. The next prime is 55242623. The reversal of 55242621 is 12624255.

It is not a de Polignac number, because 55242621 - 2³ = 55242613 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55242623) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4185 + ... + 11313.

It is an arithmetic number, because the mean of its divisors is an integer number (2994600).

Almost surely, 2^55242621 is an apocalyptic number.

It is an amenable number.

55242621 is a deficient number, since it is larger than the sum of its proper divisors (40584579).

55242621 is a wasteful number, since it uses less digits than its factorization.

55242621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7186 (or 7180 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 55242621 is about 7432.5379918302. The cubic root of 55242621 is about 380.8536234781.

Adding to 55242621 its reverse (12624255), we get a palindrome (67866876).

The spelling of 55242621 in words is "fifty-five million, two hundred forty-two thousand, six hundred twenty-one".