55215500 has 24 divisors (see below), whose sum is σ = 120591744. Its totient is φ = 22086000.

The previous prime is 55215497. The next prime is 55215509. The reversal of 55215500 is 551255.

55215500 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

55215500 is strictly pandigital in base 9.

It is not an unprimeable number, because it can be changed into a prime (55215509) 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, 54716 + ... + 55715.

It is an arithmetic number, because the mean of its divisors is an integer number (5024656).

Almost surely, 2^55215500 is an apocalyptic number.

55215500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

55215500 is an abundant number, since it is smaller than the sum of its proper divisors (65376244).

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

55215500 is a wasteful number, since it uses less digits than its factorization.

55215500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110450 (or 110438 counting only the distinct ones).

The product of its (nonzero) digits is 1250, while the sum is 23.

The square root of 55215500 is about 7430.7132901223. The cubic root of 55215500 is about 380.7912874186.

Adding to 55215500 its reverse (551255), we get a palindrome (55766755).

The spelling of 55215500 in words is "fifty-five million, two hundred fifteen thousand, five hundred".