129121000 has 32 divisors (see below), whose sum is σ = 302145480. Its totient is φ = 51648000.

The previous prime is 129120989. The next prime is 129121007. The reversal of 129121000 is 121921.

It can be written as a sum of positive squares in 4 ways, for example, as 23483716 + 105637284 = 4846^2 + 10278^2 .

It is not an unprimeable number, because it can be changed into a prime (129121007) 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, 63561 + ... + 65560.

Almost surely, 2^129121000 is an apocalyptic number.

129121000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129121000 is an abundant number, since it is smaller than the sum of its proper divisors (173024480).

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

129121000 is a wasteful number, since it uses less digits than its factorization.

129121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129142 (or 129128 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 129121000 is about 11363.1421710722. The cubic root of 129121000 is about 505.4353661521.

Adding to 129121000 its reverse (121921), we get a palindrome (129242921).

The spelling of 129121000 in words is "one hundred twenty-nine million, one hundred twenty-one thousand".