129994172 has 144 divisors (see below), whose sum is σ = 315854784. Its totient is φ = 45619200.

The previous prime is 129994157. The next prime is 129994187. The reversal of 129994172 is 271499921.

It is an interprime number because it is at equal distance from previous prime (129994157) and next prime (129994187).

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2131022 + ... + 2131082.

It is an arithmetic number, because the mean of its divisors is an integer number (2193436).

Almost surely, 2^129994172 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129994172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157927392).

129994172 is an abundant number, since it is smaller than the sum of its proper divisors (185860612).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129994172 is a wasteful number, since it uses less digits than its factorization.

129994172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 135 counting only the distinct ones).

The product of its digits is 81648, while the sum is 44.

The square root of 129994172 is about 11401.4986734201. The cubic root of 129994172 is about 506.5721316777.

It can be divided in two parts, 12999 and 4172, that added together give a palindrome (17171).

The spelling of 129994172 in words is "one hundred twenty-nine million, nine hundred ninety-four thousand, one hundred seventy-two".