55558440 has 128 divisors (see below), whose sum is σ = 211680000. Its totient is φ = 12697344.

The previous prime is 55558429. The next prime is 55558483. The reversal of 55558440 is 4485555.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 55558395 and 55558404.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3886 + ... + 11234.

It is an arithmetic number, because the mean of its divisors is an integer number (1653750).

Almost surely, 2^55558440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55558440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105840000).

55558440 is an abundant number, since it is smaller than the sum of its proper divisors (156121560).

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

55558440 is a wasteful number, since it uses less digits than its factorization.

55558440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7376 (or 7366 counting only the distinct ones).

The product of its (nonzero) digits is 80000, while the sum is 36.

The square root of 55558440 is about 7453.7534169035. The cubic root of 55558440 is about 381.5780177994.

The spelling of 55558440 in words is "fifty-five million, five hundred fifty-eight thousand, four hundred forty".