129213408 has 24 divisors (see below), whose sum is σ = 339185448. Its totient is φ = 43071104.

The previous prime is 129213407. The next prime is 129213419. The reversal of 129213408 is 804312921.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×129213408² = 33392209613948928, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129213401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 672891 + ... + 673082.

It is an arithmetic number, because the mean of its divisors is an integer number (14132727).

Almost surely, 2^129213408 is an apocalyptic number.

It is an amenable number.

129213408 is an abundant number, since it is smaller than the sum of its proper divisors (209972040).

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

129213408 is a wasteful number, since it uses less digits than its factorization.

129213408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1345986 (or 1345978 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 129213408 is about 11367.2075726627. The cubic root of 129213408 is about 505.5559123417. Note that the first 3 decimals are identical.

The spelling of 129213408 in words is "one hundred twenty-nine million, two hundred thirteen thousand, four hundred eight".