131519721 has 16 divisors (see below), whose sum is σ = 178891328. Its totient is φ = 85924800.

The previous prime is 131519699. The next prime is 131519741. The reversal of 131519721 is 127915131.

It is not a de Polignac number, because 131519721 - 2¹³ = 131511529 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131519741) 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 15 ways as a sum of consecutive naturals, for example, 55011 + ... + 57351.

It is an arithmetic number, because the mean of its divisors is an integer number (11180708).

Almost surely, 2^131519721 is an apocalyptic number.

It is an amenable number.

131519721 is a deficient number, since it is larger than the sum of its proper divisors (47371607).

131519721 is a wasteful number, since it uses less digits than its factorization.

131519721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2712.

The product of its digits is 1890, while the sum is 30.

The square root of 131519721 is about 11468.2047854056. The cubic root of 131519721 is about 508.5460588722.

The spelling of 131519721 in words is "one hundred thirty-one million, five hundred nineteen thousand, seven hundred twenty-one".