129091836 has 12 divisors (see below), whose sum is σ = 301214312. Its totient is φ = 43030608.

The previous prime is 129091819. The next prime is 129091841. The reversal of 129091836 is 638190921.

It is a tau number, because it is divible by the number of its divisors (12).

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 129091794 and 129091803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5378815 + ... + 5378838.

Almost surely, 2^129091836 is an apocalyptic number.

It is an amenable number.

129091836 is an abundant number, since it is smaller than the sum of its proper divisors (172122476).

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

129091836 is a wasteful number, since it uses less digits than its factorization.

129091836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10757660 (or 10757658 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 129091836 is about 11361.8588267941. The cubic root of 129091836 is about 505.3973097890.

The spelling of 129091836 in words is "one hundred twenty-nine million, ninety-one thousand, eight hundred thirty-six".