131315021 has 8 divisors (see below), whose sum is σ = 139277304. Its totient is φ = 123379200.

The previous prime is 131315003. The next prime is 131315029. The reversal of 131315021 is 120513131.

It can be written as a sum of positive squares in 4 ways, for example, as 1240996 + 130074025 = 1114^2 + 11405^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 131315021 - 2²⁶ = 64206157 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131315029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4121 + ... + 16721.

It is an arithmetic number, because the mean of its divisors is an integer number (17409663).

Almost surely, 2^131315021 is an apocalyptic number.

It is an amenable number.

131315021 is a deficient number, since it is larger than the sum of its proper divisors (7962283).

131315021 is a wasteful number, since it uses less digits than its factorization.

131315021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13231.

The product of its (nonzero) digits is 90, while the sum is 17.

The square root of 131315021 is about 11459.2766351110. The cubic root of 131315021 is about 508.2820846898.

Adding to 131315021 its reverse (120513131), we get a palindrome (251828152).

The spelling of 131315021 in words is "one hundred thirty-one million, three hundred fifteen thousand, twenty-one".