20110129998 has 128 divisors (see below), whose sum is σ = 47502167040. Its totient is φ = 5557939200.

The previous prime is 20110129997. The next prime is 20110130021. The reversal of 20110129998 is 89992101102.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20110129993) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 49168818 + ... + 49169226.

It is an arithmetic number, because the mean of its divisors is an integer number (371110680).

Almost surely, 2^20110129998 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20110129998, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23751083520).

20110129998 is an abundant number, since it is smaller than the sum of its proper divisors (27392037042).

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

20110129998 is a wasteful number, since it uses less digits than its factorization.

20110129998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762.

The product of its (nonzero) digits is 23328, while the sum is 42.

The spelling of 20110129998 in words is "twenty billion, one hundred ten million, one hundred twenty-nine thousand, nine hundred ninety-eight".