129420100 has 18 divisors (see below), whose sum is σ = 280841834. Its totient is φ = 51768000.

The previous prime is 129420079. The next prime is 129420107. The reversal of 129420100 is 1024921.

It can be written as a sum of positive squares in 3 ways, for example, as 6724 + 129413376 = 82^2 + 11376^2 .

It is not an unprimeable number, because it can be changed into a prime (129420107) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 647001 + ... + 647200.

Almost surely, 2^129420100 is an apocalyptic number.

129420100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129420100 is an abundant number, since it is smaller than the sum of its proper divisors (151421734).

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

129420100 is a wasteful number, since it uses less digits than its factorization.

129420100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1294215 (or 1294208 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 129420100 is about 11376.2955306198. The cubic root of 129420100 is about 505.8253340597.

The spelling of 129420100 in words is "one hundred twenty-nine million, four hundred twenty thousand, one hundred".