57571981 has 4 divisors (see below), whose sum is σ = 57587200. Its totient is φ = 57556764.

The previous prime is 57571973. The next prime is 57571999. The reversal of 57571981 is 18917575.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 57571981 - 2³ = 57571973 is a prime.

It is a super-2 number, since 2×57571981² = 6629065992528722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57571901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2950 + ... + 11128.

It is an arithmetic number, because the mean of its divisors is an integer number (14396800).

Almost surely, 2^57571981 is an apocalyptic number.

It is an amenable number.

57571981 is a deficient number, since it is larger than the sum of its proper divisors (15219).

57571981 is an equidigital number, since it uses as much as digits as its factorization.

57571981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15218.

The product of its digits is 88200, while the sum is 43.

The square root of 57571981 is about 7587.6202461641. The cubic root of 57571981 is about 386.1331232065.

The spelling of 57571981 in words is "fifty-seven million, five hundred seventy-one thousand, nine hundred eighty-one".