21002111200020 has 48 divisors (see below), whose sum is σ = 59228975494080. Its totient is φ = 5560271164416.

The previous prime is 21002111200003. The next prime is 21002111200039. The reversal of 21002111200020 is 2000211120012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21002111199969 and 21002111200005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1259111037 + ... + 1259127716.

It is an arithmetic number, because the mean of its divisors is an integer number (1233936989460).

Almost surely, 2^{21002111200020} is an apocalyptic number.

21002111200020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002111200020 is an abundant number, since it is smaller than the sum of its proper divisors (38226864294060).

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

21002111200020 is a wasteful number, since it uses less digits than its factorization.

21002111200020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2518238904 (or 2518238902 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21002111200020 its reverse (2000211120012), we get a palindrome (23002322320032).

The spelling of 21002111200020 in words is "twenty-one trillion, two billion, one hundred eleven million, two hundred thousand, twenty".