55509804 has 72 divisors (see below), whose sum is σ = 161380128. Its totient is φ = 15759360.

The previous prime is 55509803. The next prime is 55509821. The reversal of 55509804 is 40890555.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (55509803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45004 + ... + 46220.

Almost surely, 2^55509804 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 55509804, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80690064).

55509804 is an abundant number, since it is smaller than the sum of its proper divisors (105870324).

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

55509804 is a wasteful number, since it uses less digits than its factorization.

55509804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1415 (or 1410 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 55509804 is about 7450.4901852160. The cubic root of 55509804 is about 381.4666405033.

The spelling of 55509804 in words is "fifty-five million, five hundred nine thousand, eight hundred four".