129898145221 has 4 divisors (see below), whose sum is σ = 139890310252. Its totient is φ = 119905980192.

The previous prime is 129898145183. The next prime is 129898145233. The reversal of 129898145221 is 122541898921.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 81932765121 + 47965380100 = 286239^2 + 219010^2 .

It is a cyclic number.

It is not a de Polignac number, because 129898145221 - 2¹⁹ = 129897620933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129898145621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4996082496 + ... + 4996082521.

It is an arithmetic number, because the mean of its divisors is an integer number (34972577563).

Almost surely, 2^129898145221 is an apocalyptic number.

It is an amenable number.

129898145221 is a deficient number, since it is larger than the sum of its proper divisors (9992165031).

129898145221 is an equidigital number, since it uses as much as digits as its factorization.

129898145221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9992165030.

The product of its digits is 829440, while the sum is 52.

The spelling of 129898145221 in words is "one hundred twenty-nine billion, eight hundred ninety-eight million, one hundred forty-five thousand, two hundred twenty-one".