129221806 has 16 divisors (see below), whose sum is σ = 223217280. Its totient is φ = 54957240.

The previous prime is 129221779. The next prime is 129221809. The reversal of 129221806 is 608122921.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129221809) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33396 + ... + 37063.

It is an arithmetic number, because the mean of its divisors is an integer number (13951080).

Almost surely, 2^129221806 is an apocalyptic number.

129221806 is a deficient number, since it is larger than the sum of its proper divisors (93995474).

129221806 is a wasteful number, since it uses less digits than its factorization.

129221806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70599.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 129221806 is about 11367.5769625721. The cubic root of 129221806 is about 505.5668646792.

The spelling of 129221806 in words is "one hundred twenty-nine million, two hundred twenty-one thousand, eight hundred six".