57240720 has 120 divisors (see below), whose sum is σ = 194291136. Its totient is φ = 15101184.

The previous prime is 57240691. The next prime is 57240727. The reversal of 57240720 is 2704275.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×57240720² = 6553000052236800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (57240727) 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, 76669 + ... + 77411.

Almost surely, 2^57240720 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 57240720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97145568).

57240720 is an abundant number, since it is smaller than the sum of its proper divisors (137050416).

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

57240720 is a wasteful number, since it uses less digits than its factorization.

57240720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 869 (or 860 counting only the distinct ones).

The product of its (nonzero) digits is 3920, while the sum is 27.

The square root of 57240720 is about 7565.7597106966. The cubic root of 57240720 is about 385.3911131958.

Adding to 57240720 its reverse (2704275), we get a palindrome (59944995).

The spelling of 57240720 in words is "fifty-seven million, two hundred forty thousand, seven hundred twenty".