57180721 has 8 divisors (see below), whose sum is σ = 63703080. Its totient is φ = 50961792.

The previous prime is 57180719. The next prime is 57180727. The reversal of 57180721 is 12708175.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5340721 + 51840000 = 2311^2 + 7200^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 57180721 - 2¹ = 57180719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (57180727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75460 + ... + 76213.

It is an arithmetic number, because the mean of its divisors is an integer number (7962885).

Almost surely, 2^57180721 is an apocalyptic number.

It is an amenable number.

57180721 is a deficient number, since it is larger than the sum of its proper divisors (6522359).

57180721 is a wasteful number, since it uses less digits than its factorization.

57180721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151715.

The product of its (nonzero) digits is 3920, while the sum is 31.

The square root of 57180721 is about 7561.7935041893. The cubic root of 57180721 is about 385.2564120879.

Adding to 57180721 its reverse (12708175), we get a palindrome (69888896).

The spelling of 57180721 in words is "fifty-seven million, one hundred eighty thousand, seven hundred twenty-one".