131305520 has 40 divisors (see below), whose sum is σ = 305836080. Its totient is φ = 52427520.

The previous prime is 131305513. The next prime is 131305529. The reversal of 131305520 is 25503131.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×131305520² = 34482279164940800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 131305492 and 131305501.

It is not an unprimeable number, because it can be changed into a prime (131305529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58010 + ... + 60230.

It is an arithmetic number, because the mean of its divisors is an integer number (7645902).

Almost surely, 2^131305520 is an apocalyptic number.

131305520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

131305520 is an abundant number, since it is smaller than the sum of its proper divisors (174530560).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

131305520 is a wasteful number, since it uses less digits than its factorization.

131305520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2973 (or 2967 counting only the distinct ones).

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 131305520 is about 11458.8620726493. The cubic root of 131305520 is about 508.2698258623.

Adding to 131305520 its reverse (25503131), we get a palindrome (156808651).

The spelling of 131305520 in words is "one hundred thirty-one million, three hundred five thousand, five hundred twenty".