21012122201020 has 24 divisors (see below), whose sum is σ = 44162819463168. Its totient is φ = 8397732148800.

The previous prime is 21012122201003. The next prime is 21012122201053. The reversal of 21012122201020 is 2010222121012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21012122200985 and 21012122201003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 444771516 + ... + 444818755.

It is an arithmetic number, because the mean of its divisors is an integer number (1840117477632).

Almost surely, 2^{21012122201020} is an apocalyptic number.

21012122201020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21012122201020 is an abundant number, since it is smaller than the sum of its proper divisors (23150697262148).

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

21012122201020 is a wasteful number, since it uses less digits than its factorization.

21012122201020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 889591461 (or 889591459 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21012122201020 its reverse (2010222121012), we get a palindrome (23022344322032).

The spelling of 21012122201020 in words is "twenty-one trillion, twelve billion, one hundred twenty-two million, two hundred one thousand, twenty".