129449920 has 28 divisors (see below), whose sum is σ = 308253384. Its totient is φ = 51779840.

The previous prime is 129449899. The next prime is 129449921. The reversal of 129449920 is 29944921.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129449921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 201946 + ... + 202585.

Almost surely, 2^129449920 is an apocalyptic number.

129449920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129449920 is an abundant number, since it is smaller than the sum of its proper divisors (178803464).

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

129449920 is an equidigital number, since it uses as much as digits as its factorization.

129449920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404548 (or 404538 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 129449920 is about 11377.6060750933. The cubic root of 129449920 is about 505.8641805580.

The spelling of 129449920 in words is "one hundred twenty-nine million, four hundred forty-nine thousand, nine hundred twenty".