57249720 has 256 divisors, whose sum is σ = 214272000. Its totient is φ = 13478400.

The previous prime is 57249719. The next prime is 57249721. The reversal of 57249720 is 2794275.

It is an interprime number because it is at equal distance from previous prime (57249719) and next prime (57249721).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57249721) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 724641 + ... + 724719.

It is an arithmetic number, because the mean of its divisors is an integer number (837000).

Almost surely, 2^57249720 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 57249720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107136000).

57249720 is an abundant number, since it is smaller than the sum of its proper divisors (157022280).

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

57249720 is a wasteful number, since it uses less digits than its factorization.

57249720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 57249720 is about 7566.3544722673. The cubic root of 57249720 is about 385.4113105789.

Subtracting from 57249720 its reverse (2794275), we obtain a palindrome (54455445).

The spelling of 57249720 in words is "fifty-seven million, two hundred forty-nine thousand, seven hundred twenty".