21012020221100 has 18 divisors (see below), whose sum is σ = 45596083880004. Its totient is φ = 8404808088400.

The previous prime is 21012020221099. The next prime is 21012020221103. The reversal of 21012020221100 is 112202021012.

It is not an unprimeable number, because it can be changed into a prime (21012020221103) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105060101006 + ... + 105060101205.

Almost surely, 2^{21012020221100} is an apocalyptic number.

21012020221100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21012020221100 is an abundant number, since it is smaller than the sum of its proper divisors (24584063658904).

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

21012020221100 is a wasteful number, since it uses less digits than its factorization.

21012020221100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210120202225 (or 210120202218 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21012020221100 its reverse (112202021012), we get a palindrome (21124222242112).

The spelling of 21012020221100 in words is "twenty-one trillion, twelve billion, twenty million, two hundred twenty-one thousand, one hundred".