521660131 has 2 divisors, whose sum is σ = 521660132. Its totient is φ = 521660130.

The previous prime is 521660119. The next prime is 521660141. The reversal of 521660131 is 131066125.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 521660131 - 2⁵ = 521660099 is a prime.

It is a super-2 number, since 2×521660131² = 544258584549874322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 521660096 and 521660105.

It is not a weakly prime, because it can be changed into another prime (521660141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260830065 + 260830066.

It is an arithmetic number, because the mean of its divisors is an integer number (260830066).

Almost surely, 2^521660131 is an apocalyptic number.

521660131 is a deficient number, since it is larger than the sum of its proper divisors (1).

521660131 is an equidigital number, since it uses as much as digits as its factorization.

521660131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 521660131 is about 22839.8802755181. The cubic root of 521660131 is about 805.0000030863. Note that the first 5 decimals are identical.

The spelling of 521660131 in words is "five hundred twenty-one million, six hundred sixty thousand, one hundred thirty-one".