53131021 has 4 divisors (see below), whose sum is σ = 53221212. Its totient is φ = 53040832.

The previous prime is 53131019. The next prime is 53131027. The reversal of 53131021 is 12013135.

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 45765225 + 7365796 = 6765^2 + 2714^2 .

It is a cyclic number.

It is not a de Polignac number, because 53131021 - 2¹ = 53131019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 53130986 and 53131004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53131027) 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, 44206 + ... + 45391.

It is an arithmetic number, because the mean of its divisors is an integer number (13305303).

Almost surely, 2^53131021 is an apocalyptic number.

It is an amenable number.

53131021 is a deficient number, since it is larger than the sum of its proper divisors (90191).

53131021 is an equidigital number, since it uses as much as digits as its factorization.

53131021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90190.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 53131021 is about 7289.1028940467. The cubic root of 53131021 is about 375.9378504679.

Adding to 53131021 its reverse (12013135), we get a palindrome (65144156).

The spelling of 53131021 in words is "fifty-three million, one hundred thirty-one thousand, twenty-one".