31729139 has 8 divisors (see below), whose sum is σ = 34815312. Its totient is φ = 28735200.

The previous prime is 31729133. The next prime is 31729163. The reversal of 31729139 is 93192713.

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-31729139 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31729099 and 31729108.

It is not an unprimeable number, because it can be changed into a prime (31729133) 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, 22337 + ... + 23714.

It is an arithmetic number, because the mean of its divisors is an integer number (4351914).

Almost surely, 2^31729139 is an apocalyptic number.

31729139 is a deficient number, since it is larger than the sum of its proper divisors (3086173).

31729139 is a wasteful number, since it uses less digits than its factorization.

31729139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46117.

The product of its digits is 10206, while the sum is 35.

The square root of 31729139 is about 5632.8624162143. The cubic root of 31729139 is about 316.5819105888.

The spelling of 31729139 in words is "thirty-one million, seven hundred twenty-nine thousand, one hundred thirty-nine".