129181749 has 16 divisors (see below), whose sum is σ = 175156224. Its totient is φ = 84672000.

The previous prime is 129181729. The next prime is 129181751. The reversal of 129181749 is 947181921.

It is not a de Polignac number, because 129181749 - 2⁹ = 129181237 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129181749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129181729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87084 + ... + 88554.

It is an arithmetic number, because the mean of its divisors is an integer number (10947264).

Almost surely, 2^129181749 is an apocalyptic number.

It is an amenable number.

129181749 is a deficient number, since it is larger than the sum of its proper divisors (45974475).

129181749 is a wasteful number, since it uses less digits than its factorization.

129181749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1948.

The product of its digits is 36288, while the sum is 42.

The square root of 129181749 is about 11365.8149289877. The cubic root of 129181749 is about 505.5146196662.

The spelling of 129181749 in words is "one hundred twenty-nine million, one hundred eighty-one thousand, seven hundred forty-nine".