129292820 has 36 divisors (see below), whose sum is σ = 288438780. Its totient is φ = 48672768.

The previous prime is 129292799. The next prime is 129292829. The reversal of 129292820 is 28292921.

It can be written as a sum of positive squares in 6 ways, for example, as 5326864 + 123965956 = 2308^2 + 11134^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129292829) 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, 5405 + ... + 16964.

Almost surely, 2^129292820 is an apocalyptic number.

129292820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129292820 is an abundant number, since it is smaller than the sum of its proper divisors (159145960).

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

129292820 is a wasteful number, since it uses less digits than its factorization.

129292820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22412 (or 22393 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 129292820 is about 11370.7000663987. The cubic root of 129292820 is about 505.6594593471.

The spelling of 129292820 in words is "one hundred twenty-nine million, two hundred ninety-two thousand, eight hundred twenty".