20123312100 has 144 divisors (see below), whose sum is σ = 61727049216. Its totient is φ = 5052672000.

The previous prime is 20123312089. The next prime is 20123312117. The reversal of 20123312100 is 121332102.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20123312100.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 314860 + ... + 373340.

It is an arithmetic number, because the mean of its divisors is an integer number (428660064).

Almost surely, 2^20123312100 is an apocalyptic number.

20123312100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20123312100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30863524608).

20123312100 is an abundant number, since it is smaller than the sum of its proper divisors (41603737116).

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

20123312100 is a wasteful number, since it uses less digits than its factorization.

20123312100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58566 (or 58559 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 20123312100 its reverse (121332102), we get a palindrome (20244644202).

The spelling of 20123312100 in words is "twenty billion, one hundred twenty-three million, three hundred twelve thousand, one hundred".