57261 has 4 divisors (see below), whose sum is σ = 76352. Its totient is φ = 38172.

The previous prime is 57259. The next prime is 57269. The reversal of 57261 is 16275.

Added to its reverse (16275) it gives a triangular number (73536 = T₃₈₃).

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 57261 - 2¹ = 57259 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57269) 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, 9541 + ... + 9546.

It is an arithmetic number, because the mean of its divisors is an integer number (19088).

2⁵⁷²⁶¹ is an apocalyptic number.

It is an amenable number.

57261 is a deficient number, since it is larger than the sum of its proper divisors (19091).

57261 is a wasteful number, since it uses less digits than its factorization.

57261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19090.

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

The square root of 57261 is about 239.2927077869. The cubic root of 57261 is about 38.5436621644.

Adding to 57261 its reverse (16275), we get a triangular number (73536 = T₃₈₃).

The spelling of 57261 in words is "fifty-seven thousand, two hundred sixty-one".