129691828 has 36 divisors (see below), whose sum is σ = 273131460. Its totient is φ = 53663232.

The previous prime is 129691823. The next prime is 129691829. The reversal of 129691828 is 828196921.

It can be written as a sum of positive squares in 2 ways, for example, as 109369764 + 20322064 = 10458^2 + 4508^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129691823) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5725 + ... + 17092.

It is an arithmetic number, because the mean of its divisors is an integer number (7586985).

Almost surely, 2^129691828 is an apocalyptic number.

It is an amenable number.

129691828 is an abundant number, since it is smaller than the sum of its proper divisors (143439632).

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

129691828 is a wasteful number, since it uses less digits than its factorization.

129691828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22864 (or 22855 counting only the distinct ones).

The product of its digits is 124416, while the sum is 46.

The square root of 129691828 is about 11388.2319962319. The cubic root of 129691828 is about 506.1790937018.

The spelling of 129691828 in words is "one hundred twenty-nine million, six hundred ninety-one thousand, eight hundred twenty-eight".