129010121 has 4 divisors (see below), whose sum is σ = 129332244. Its totient is φ = 128688000.

The previous prime is 129010117. The next prime is 129010129. The reversal of 129010121 is 121010921.

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 69488896 + 59521225 = 8336^2 + 7715^2 .

It is a cyclic number.

It is not a de Polignac number, because 129010121 - 2² = 129010117 is a prime.

It is a super-2 number, since 2×129010121² = 33287222640869282, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129010121.

It is not an unprimeable number, because it can be changed into a prime (129010129) 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 3 ways as a sum of consecutive naturals, for example, 160460 + ... + 161261.

It is an arithmetic number, because the mean of its divisors is an integer number (32333061).

Almost surely, 2^129010121 is an apocalyptic number.

It is an amenable number.

129010121 is a deficient number, since it is larger than the sum of its proper divisors (322123).

129010121 is an equidigital number, since it uses as much as digits as its factorization.

129010121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322122.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 129010121 is about 11358.2622350428. The cubic root of 129010121 is about 505.2906486205.

It can be divided in two parts, 1290 and 10121, that added together give a palindrome (11411).

The spelling of 129010121 in words is "one hundred twenty-nine million, ten thousand, one hundred twenty-one".