57721613 has 8 divisors (see below), whose sum is σ = 61585920. Its totient is φ = 53909440.

The previous prime is 57721589. The next prime is 57721637. The reversal of 57721613 is 31612775.

It is an interprime number because it is at equal distance from previous prime (57721589) and next prime (57721637).

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 57721613 - 2⁶ = 57721549 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 57721613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57721663) 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, 10733 + ... + 15186.

It is an arithmetic number, because the mean of its divisors is an integer number (7698240).

Almost surely, 2^57721613 is an apocalyptic number.

It is an amenable number.

57721613 is a deficient number, since it is larger than the sum of its proper divisors (3864307).

57721613 is a wasteful number, since it uses less digits than its factorization.

57721613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26067.

The product of its digits is 8820, while the sum is 32.

The square root of 57721613 is about 7597.4741197322. The cubic root of 57721613 is about 386.4673592181.

The spelling of 57721613 in words is "fifty-seven million, seven hundred twenty-one thousand, six hundred thirteen".