57824721 has 6 divisors (see below), whose sum is σ = 83524610. Its totient is φ = 38549808.

The previous prime is 57824717. The next prime is 57824759. The reversal of 57824721 is 12742875.

It can be written as a sum of positive squares in only one way, i.e., 50339025 + 7485696 = 7095^2 + 2736^2 .

It is not a de Polignac number, because 57824721 - 2² = 57824717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (57824791) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3212476 + ... + 3212493.

Almost surely, 2^57824721 is an apocalyptic number.

It is an amenable number.

57824721 is a deficient number, since it is larger than the sum of its proper divisors (25699889).

57824721 is a wasteful number, since it uses less digits than its factorization.

57824721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6424975 (or 6424972 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 57824721 is about 7604.2567684160. The cubic root of 57824721 is about 386.6973376219.

The spelling of 57824721 in words is "fifty-seven million, eight hundred twenty-four thousand, seven hundred twenty-one".