21100022012020 has 192 divisors, whose sum is σ = 52626608133120. Its totient is φ = 6955690291200.

The previous prime is 21100022011927. The next prime is 21100022012053. The reversal of 21100022012020 is 2021022000112.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1205087026 + ... + 1205104534.

It is an arithmetic number, because the mean of its divisors is an integer number (274096917360).

Almost surely, 2^{21100022012020} is an apocalyptic number.

21100022012020 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 21100022012020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26313304066560).

21100022012020 is an abundant number, since it is smaller than the sum of its proper divisors (31526586121100).

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

21100022012020 is a wasteful number, since it uses less digits than its factorization.

21100022012020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20594 (or 20592 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21100022012020 its reverse (2021022000112), we get a palindrome (23121044012132).

The spelling of 21100022012020 in words is "twenty-one trillion, one hundred billion, twenty-two million, twelve thousand, twenty".