10131521 has 4 divisors (see below), whose sum is σ = 10139844. Its totient is φ = 10123200.

The previous prime is 10131491. The next prime is 10131529. The reversal of 10131521 is 12513101.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 6071296 + 4060225 = 2464^2 + 2015^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10131521 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 = 10131496 and 10131505.

It is not an unprimeable number, because it can be changed into a prime (10131529) 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, 1940 + ... + 4901.

It is an arithmetic number, because the mean of its divisors is an integer number (2534961).

Almost surely, 2^10131521 is an apocalyptic number.

It is an amenable number.

10131521 is a deficient number, since it is larger than the sum of its proper divisors (8323).

10131521 is an equidigital number, since it uses as much as digits as its factorization.

10131521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8322.

The product of its (nonzero) digits is 30, while the sum is 14.

The square root of 10131521 is about 3183.0050267004. The cubic root of 10131521 is about 216.3838695762.

Adding to 10131521 its reverse (12513101), we get a palindrome (22644622).

The spelling of 10131521 in words is "ten million, one hundred thirty-one thousand, five hundred twenty-one".