51555500 has 48 divisors (see below), whose sum is σ = 113865024. Its totient is φ = 20390400.

The previous prime is 51555499. The next prime is 51555521. The reversal of 51555500 is 555515.

It is a self number, because there is not a number n which added to its sum of digits gives 51555500.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47969 + ... + 49031.

It is an arithmetic number, because the mean of its divisors is an integer number (2372188).

Almost surely, 2^51555500 is an apocalyptic number.

51555500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51555500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56932512).

51555500 is an abundant number, since it is smaller than the sum of its proper divisors (62309524).

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

51555500 is a wasteful number, since it uses less digits than its factorization.

51555500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1179 (or 1167 counting only the distinct ones).

The product of its (nonzero) digits is 3125, while the sum is 26.

The square root of 51555500 is about 7180.2158741921. The cubic root of 51555500 is about 372.1845444235.

The spelling of 51555500 in words is "fifty-one million, five hundred fifty-five thousand, five hundred".