129121628 has 24 divisors (see below), whose sum is σ = 235287024. Its totient is φ = 61948800.

The previous prime is 129121627. The next prime is 129121631. The reversal of 129121628 is 826121921.

It is a junction number, because it is equal to n+sod(n) for n = 129121594 and 129121603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129121627) 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, 3551 + ... + 16457.

It is an arithmetic number, because the mean of its divisors is an integer number (9803626).

Almost surely, 2^129121628 is an apocalyptic number.

It is an amenable number.

129121628 is a deficient number, since it is larger than the sum of its proper divisors (106165396).

129121628 is a wasteful number, since it uses less digits than its factorization.

129121628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13013 (or 13011 counting only the distinct ones).

The product of its digits is 3456, while the sum is 32.

The square root of 129121628 is about 11363.1698042404. The cubic root of 129121628 is about 505.4361855718.

The spelling of 129121628 in words is "one hundred twenty-nine million, one hundred twenty-one thousand, six hundred twenty-eight".