131503501521 has 18 divisors (see below), whose sum is σ = 220961666562. Its totient is φ = 75144857760.

The previous prime is 131503501511. The next prime is 131503501561. The reversal of 131503501521 is 125105305131.

131503501521 is a `hidden beast` number, since 1 + 3 + 1 + 503 + 5 + 0 + 152 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 102103255296 + 29400246225 = 319536^2 + 171465^2 .

It is not a de Polignac number, because 131503501521 - 2⁹ = 131503501009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (131503501511) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 149096500 + ... + 149097381.

Almost surely, 2^131503501521 is an apocalyptic number.

It is an amenable number.

131503501521 is a deficient number, since it is larger than the sum of its proper divisors (89458165041).

131503501521 is a wasteful number, since it uses less digits than its factorization.

131503501521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298193901 (or 298193891 counting only the distinct ones).

The product of its (nonzero) digits is 2250, while the sum is 27.

Adding to 131503501521 its reverse (125105305131), we get a palindrome (256608806652).

The spelling of 131503501521 in words is "one hundred thirty-one billion, five hundred three million, five hundred one thousand, five hundred twenty-one".