130131721 has 4 divisors (see below), whose sum is σ = 131325700. Its totient is φ = 128937744.

The previous prime is 130131713. The next prime is 130131737. The reversal of 130131721 is 127131031.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35283600 + 94848121 = 5940^2 + 9739^2 .

It is a cyclic number.

It is not a de Polignac number, because 130131721 - 2³ = 130131713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (130131791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 596826 + ... + 597043.

It is an arithmetic number, because the mean of its divisors is an integer number (32831425).

Almost surely, 2^130131721 is an apocalyptic number.

It is an amenable number.

130131721 is a deficient number, since it is larger than the sum of its proper divisors (1193979).

130131721 is a wasteful number, since it uses less digits than its factorization.

130131721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1193978.

The product of its (nonzero) digits is 126, while the sum is 19.

The square root of 130131721 is about 11407.5291364958. The cubic root of 130131721 is about 506.7507395017.

Adding to 130131721 its reverse (127131031), we get a palindrome (257262752).

It can be divided in two parts, 130131 and 721, that multiplied together give a triangular number (93824451 = T₁₃₆₉₈).

The spelling of 130131721 in words is "one hundred thirty million, one hundred thirty-one thousand, seven hundred twenty-one".