131023521 has 16 divisors (see below), whose sum is σ = 194353600. Its totient is φ = 87238944.

The previous prime is 131023513. The next prime is 131023523. The reversal of 131023521 is 125320131.

131023521 = T₁₇₅₈ + T₁₇₅₉ + ... + T₁₈₃₈.

131023521 is a `hidden beast` number, since 1 + 310 + 2 + 352 + 1 = 666.

It is not a de Polignac number, because 131023521 - 2³ = 131023513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131023494 and 131023503.

It is not an unprimeable number, because it can be changed into a prime (131023523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22710 + ... + 27888.

It is an arithmetic number, because the mean of its divisors is an integer number (12147100).

Almost surely, 2^131023521 is an apocalyptic number.

It is an amenable number.

131023521 is a deficient number, since it is larger than the sum of its proper divisors (63330079).

131023521 is an equidigital number, since it uses as much as digits as its factorization.

131023521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6125 (or 6119 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 131023521 is about 11446.5506157969. The cubic root of 131023521 is about 507.9057022668.

Adding to 131023521 its reverse (125320131), we get a palindrome (256343652).

The spelling of 131023521 in words is "one hundred thirty-one million, twenty-three thousand, five hundred twenty-one".