55618644 has 24 divisors (see below), whose sum is σ = 129908800. Its totient is φ = 18520704.

The previous prime is 55618639. The next prime is 55618649. The reversal of 55618644 is 44681655.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (55618639) and next prime (55618649).

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55618649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15132 + ... + 18444.

Almost surely, 2^55618644 is an apocalyptic number.

It is an amenable number.

55618644 is an abundant number, since it is smaller than the sum of its proper divisors (74290156).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55618644 is a wasteful number, since it uses less digits than its factorization.

55618644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4719 (or 4717 counting only the distinct ones).

The product of its digits is 115200, while the sum is 39.

The square root of 55618644 is about 7457.7908257070. The cubic root of 55618644 is about 381.7157960271.

The spelling of 55618644 in words is "fifty-five million, six hundred eighteen thousand, six hundred forty-four".