57215500 has 48 divisors (see below), whose sum is σ = 128052288. Its totient is φ = 22320000.

The previous prime is 57215453. The next prime is 57215503. The reversal of 57215500 is 551275.

It is a happy number.

It is a super-2 number, since 2×57215500² = 6547226880500000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (57215503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19105 + ... + 21895.

It is an arithmetic number, because the mean of its divisors is an integer number (2667756).

Almost surely, 2^57215500 is an apocalyptic number.

57215500 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 57215500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64026144).

57215500 is an abundant number, since it is smaller than the sum of its proper divisors (70836788).

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

57215500 is a wasteful number, since it uses less digits than its factorization.

57215500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2851 (or 2839 counting only the distinct ones).

The product of its (nonzero) digits is 1750, while the sum is 25.

The square root of 57215500 is about 7564.0928074687. The cubic root of 57215500 is about 385.3345043593.

Adding to 57215500 its reverse (551275), we get a palindrome (57766775).

The spelling of 57215500 in words is "fifty-seven million, two hundred fifteen thousand, five hundred".