131521403 has 8 divisors (see below), whose sum is σ = 141728496. Its totient is φ = 121327200.

The previous prime is 131521393. The next prime is 131521433. The reversal of 131521403 is 304125131.

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

It is a cyclic number.

It is not a de Polignac number, because 131521403 - 2⁴ = 131521387 is a prime.

It is not an unprimeable number, because it can be changed into a prime (131521433) 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, 33788 + ... + 37478.

It is an arithmetic number, because the mean of its divisors is an integer number (17716062).

Almost surely, 2^131521403 is an apocalyptic number.

131521403 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

131521403 is a deficient number, since it is larger than the sum of its proper divisors (10207093).

131521403 is a wasteful number, since it uses less digits than its factorization.

131521403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6445.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 131521403 is about 11468.2781183576. The cubic root of 131521403 is about 508.5482267875.

Adding to 131521403 its reverse (304125131), we get a palindrome (435646534).

The spelling of 131521403 in words is "one hundred thirty-one million, five hundred twenty-one thousand, four hundred three".