129891793 has 8 divisors (see below), whose sum is σ = 134303400. Its totient is φ = 125527680.

The previous prime is 129891779. The next prime is 129891803. The reversal of 129891793 is 397198921.

It can be written as a sum of positive squares in 4 ways, for example, as 7745089 + 122146704 = 2783^2 + 11052^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-129891793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129891193) 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, 6268 + ... + 17293.

It is an arithmetic number, because the mean of its divisors is an integer number (16787925).

Almost surely, 2^129891793 is an apocalyptic number.

It is an amenable number.

129891793 is a deficient number, since it is larger than the sum of its proper divisors (4411607).

129891793 is a wasteful number, since it uses less digits than its factorization.

129891793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23747.

The product of its digits is 244944, while the sum is 49.

The square root of 129891793 is about 11397.0080722969. The cubic root of 129891793 is about 506.4391104085.

The spelling of 129891793 in words is "one hundred twenty-nine million, eight hundred ninety-one thousand, seven hundred ninety-three".