129231237 has 4 divisors (see below), whose sum is σ = 172308320. Its totient is φ = 86154156.

The previous prime is 129231191. The next prime is 129231239. The reversal of 129231237 is 732132921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 129231237 - 2¹² = 129227141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129231239) 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, 21538537 + ... + 21538542.

It is an arithmetic number, because the mean of its divisors is an integer number (43077080).

Almost surely, 2^129231237 is an apocalyptic number.

It is an amenable number.

129231237 is a deficient number, since it is larger than the sum of its proper divisors (43077083).

129231237 is an equidigital number, since it uses as much as digits as its factorization.

129231237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43077082.

The product of its digits is 4536, while the sum is 30.

The square root of 129231237 is about 11367.9917751554. The cubic root of 129231237 is about 505.5791636486.

The spelling of 129231237 in words is "one hundred twenty-nine million, two hundred thirty-one thousand, two hundred thirty-seven".