21011022000020 has 96 divisors (see below), whose sum is σ = 49991764981536. Its totient is φ = 7364138803200.

The previous prime is 21011021999977. The next prime is 21011022000049. The reversal of 21011022000020 is 2000022011012.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 3573014818564 + 17438007181456 = 1890242^2 + 4175884^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21011021999965 and 21011022000010.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26240921 + ... + 27029760.

It is an arithmetic number, because the mean of its divisors is an integer number (520747551891).

Almost surely, 2^{21011022000020} is an apocalyptic number.

21011022000020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011022000020 is an abundant number, since it is smaller than the sum of its proper divisors (28980742981516).

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

21011022000020 is a wasteful number, since it uses less digits than its factorization.

21011022000020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53270781 (or 53270779 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21011022000020 its reverse (2000022011012), we get a palindrome (23011044011032).

The spelling of 21011022000020 in words is "twenty-one trillion, eleven billion, twenty-two million, twenty", and thus it is an aban number and an uban number.