21071712100 has 72 divisors (see below), whose sum is σ = 46944995328. Its totient is φ = 8205811200.

The previous prime is 21071712097. The next prime is 21071712133. The reversal of 21071712100 is 121717012.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 885964 + ... + 909436.

It is an arithmetic number, because the mean of its divisors is an integer number (652013824).

Almost surely, 2^21071712100 is an apocalyptic number.

21071712100 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 21071712100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23472497664).

21071712100 is an abundant number, since it is smaller than the sum of its proper divisors (25873283228).

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

21071712100 is a wasteful number, since it uses less digits than its factorization.

21071712100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23725 (or 23718 counting only the distinct ones).

The product of its (nonzero) digits is 196, while the sum is 22.

The spelling of 21071712100 in words is "twenty-one billion, seventy-one million, seven hundred twelve thousand, one hundred".