129689784 has 48 divisors (see below), whose sum is σ = 401422320. Its totient is φ = 37054080.

The previous prime is 129689783. The next prime is 129689789. The reversal of 129689784 is 487986921.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 129689784.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129689783) 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, 128157 + ... + 129164.

It is an arithmetic number, because the mean of its divisors is an integer number (8362965).

Almost surely, 2^129689784 is an apocalyptic number.

129689784 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

129689784 is an abundant number, since it is smaller than the sum of its proper divisors (271732536).

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

129689784 is a wasteful number, since it uses less digits than its factorization.

129689784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257340 (or 257333 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The square root of 129689784 is about 11388.1422541168. The cubic root of 129689784 is about 506.1764344864.

The spelling of 129689784 in words is "one hundred twenty-nine million, six hundred eighty-nine thousand, seven hundred eighty-four".