129949931 has 4 divisors (see below), whose sum is σ = 135599952. Its totient is φ = 124299912.

The previous prime is 129949889. The next prime is 129949961. The reversal of 129949931 is 139949921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 139949921 = 61 ⋅2294261.

It is not a de Polignac number, because 129949931 - 2¹⁴ = 129933547 is a prime.

It is a super-2 number, since 2×129949931² = 33773969133809522, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (129949961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2824976 + ... + 2825021.

It is an arithmetic number, because the mean of its divisors is an integer number (33899988).

Almost surely, 2^129949931 is an apocalyptic number.

129949931 is a deficient number, since it is larger than the sum of its proper divisors (5650021).

129949931 is an equidigital number, since it uses as much as digits as its factorization.

129949931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5650020.

The product of its digits is 157464, while the sum is 47.

The square root of 129949931 is about 11399.5583686387. The cubic root of 129949931 is about 506.5146578176.

The spelling of 129949931 in words is "one hundred twenty-nine million, nine hundred forty-nine thousand, nine hundred thirty-one".