20129117 has 8 divisors (see below), whose sum is σ = 21493824. Its totient is φ = 18805248.

The previous prime is 20129111. The next prime is 20129129. The reversal of 20129117 is 71192102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20129117 - 2⁸ = 20128861 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20129092 and 20129101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20129111) 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 7 ways as a sum of consecutive naturals, for example, 9188 + ... + 11165.

It is an arithmetic number, because the mean of its divisors is an integer number (2686728).

Almost surely, 2^20129117 is an apocalyptic number.

It is an amenable number.

20129117 is a deficient number, since it is larger than the sum of its proper divisors (1364707).

20129117 is a wasteful number, since it uses less digits than its factorization.

20129117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20419.

The product of its (nonzero) digits is 252, while the sum is 23.

The square root of 20129117 is about 4486.5484506467. The cubic root of 20129117 is about 272.0246382310.

The spelling of 20129117 in words is "twenty million, one hundred twenty-nine thousand, one hundred seventeen".