57621 has 4 divisors (see below), whose sum is σ = 76832. Its totient is φ = 38412.

The previous prime is 57601. The next prime is 57637. The reversal of 57621 is 12675.

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.

It is not a de Polignac number, because 57621 - 2⁶ = 57557 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 57621.

It is not an unprimeable number, because it can be changed into a prime (57601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9601 + ... + 9606.

It is an arithmetic number, because the mean of its divisors is an integer number (19208).

2⁵⁷⁶²¹ is an apocalyptic number.

It is an amenable number.

57621 is a deficient number, since it is larger than the sum of its proper divisors (19211).

57621 is a wasteful number, since it uses less digits than its factorization.

57621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19210.

The product of its digits is 420, while the sum is 21.

The square root of 57621 is about 240.0437460131. The cubic root of 57621 is about 38.6242681651.

Subtracting from 57621 its sum of digits (21), we obtain a square (57600 = 240²).

It can be divided in two parts, 5 and 7621, that added together give a triangular number (7626 = T₁₂₃).

The spelling of 57621 in words is "fifty-seven thousand, six hundred twenty-one".