57881821 has 8 divisors (see below), whose sum is σ = 61644024. Its totient is φ = 54159360.

The previous prime is 57881783. The next prime is 57881833. The reversal of 57881821 is 12818875.

It can be written as a sum of positive squares in 4 ways, for example, as 46389721 + 11492100 = 6811^2 + 3390^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-57881821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57881221) 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, 6900 + ... + 12781.

It is an arithmetic number, because the mean of its divisors is an integer number (7705503).

Almost surely, 2^57881821 is an apocalyptic number.

It is an amenable number.

57881821 is a deficient number, since it is larger than the sum of its proper divisors (3762203).

57881821 is a wasteful number, since it uses less digits than its factorization.

57881821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19871.

The product of its digits is 35840, while the sum is 40.

The square root of 57881821 is about 7608.0103180792. The cubic root of 57881821 is about 386.8245793603.

The spelling of 57881821 in words is "fifty-seven million, eight hundred eighty-one thousand, eight hundred twenty-one".