57311021 has 4 divisors (see below), whose sum is σ = 57346044. Its totient is φ = 57276000.

The previous prime is 57311017. The next prime is 57311027. The reversal of 57311021 is 12011375.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 40386025 + 16924996 = 6355^2 + 4114^2 .

It is a cyclic number.

It is not a de Polignac number, because 57311021 - 2² = 57311017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 57310984 and 57311002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57311027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14930 + ... + 18371.

It is an arithmetic number, because the mean of its divisors is an integer number (14336511).

Almost surely, 2^57311021 is an apocalyptic number.

It is an amenable number.

57311021 is a deficient number, since it is larger than the sum of its proper divisors (35023).

57311021 is a wasteful number, since it uses less digits than its factorization.

57311021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35022.

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 57311021 is about 7570.4042824674. The cubic root of 57311021 is about 385.5488231647.

Adding to 57311021 its reverse (12011375), we get a palindrome (69322396).

The spelling of 57311021 in words is "fifty-seven million, three hundred eleven thousand, twenty-one".