20129112 has 24 divisors (see below), whose sum is σ = 54516540. Its totient is φ = 6709680.

The previous prime is 20129111. The next prime is 20129129. The reversal of 20129112 is 21192102.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×20129112² = 810362299817088, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 139714 + ... + 139857.

Almost surely, 2^20129112 is an apocalyptic number.

It is an amenable number.

20129112 is an abundant number, since it is smaller than the sum of its proper divisors (34387428).

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

20129112 is a wasteful number, since it uses less digits than its factorization.

20129112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279583 (or 279576 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 20129112 is about 4486.5478934254. The cubic root of 20129112 is about 272.0246157076.

The spelling of 20129112 in words is "twenty million, one hundred twenty-nine thousand, one hundred twelve".