129201931 has 4 divisors (see below), whose sum is σ = 133657200. Its totient is φ = 124746664.

The previous prime is 129201913. The next prime is 129201959. The reversal of 129201931 is 139102921.

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

It is a cyclic number.

It is not a de Polignac number, because 129201931 - 2⁵ = 129201899 is a prime.

It is a super-2 number, since 2×129201931² = 33386277948257522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129201931.

It is not an unprimeable number, because it can be changed into a prime (129201901) 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 3 ways as a sum of consecutive naturals, for example, 2227591 + ... + 2227648.

It is an arithmetic number, because the mean of its divisors is an integer number (33414300).

Almost surely, 2^129201931 is an apocalyptic number.

129201931 is a deficient number, since it is larger than the sum of its proper divisors (4455269).

129201931 is an equidigital number, since it uses as much as digits as its factorization.

129201931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4455268.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 129201931 is about 11366.7027321031. The cubic root of 129201931 is about 505.5409437274.

The spelling of 129201931 in words is "one hundred twenty-nine million, two hundred one thousand, nine hundred thirty-one".