129394820 has 48 divisors (see below), whose sum is σ = 288707328. Its totient is φ = 48545280.

The previous prime is 129394817. The next prime is 129394823. The reversal of 129394820 is 28493921.

It is an interprime number because it is at equal distance from previous prime (129394817) and next prime (129394823).

It is not an unprimeable number, because it can be changed into a prime (129394823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 146099 + ... + 146981.

It is an arithmetic number, because the mean of its divisors is an integer number (6014736).

Almost surely, 2^129394820 is an apocalyptic number.

129394820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129394820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144353664).

129394820 is an abundant number, since it is smaller than the sum of its proper divisors (159312508).

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

129394820 is a wasteful number, since it uses less digits than its factorization.

129394820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340 (or 1338 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 129394820 is about 11375.1843941098. The cubic root of 129394820 is about 505.7923971430.

The spelling of 129394820 in words is "one hundred twenty-nine million, three hundred ninety-four thousand, eight hundred twenty".