55539918 has 160 divisors (see below), whose sum is σ = 156397824. Its totient is φ = 14370048.

The previous prime is 55539889. The next prime is 55539929. The reversal of 55539918 is 81993555.

55539918 is a `hidden beast` number, since 5 + 553 + 9 + 91 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 828921 + ... + 828987.

Almost surely, 2^55539918 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55539918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78198912).

55539918 is an abundant number, since it is smaller than the sum of its proper divisors (100857906).

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

55539918 is a wasteful number, since it uses less digits than its factorization.

55539918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148 (or 139 counting only the distinct ones).

The product of its digits is 243000, while the sum is 45.

The square root of 55539918 is about 7452.5108520552. The cubic root of 55539918 is about 381.5356097597.

The spelling of 55539918 in words is "fifty-five million, five hundred thirty-nine thousand, nine hundred eighteen".