21000012112020 has 24 divisors (see below), whose sum is σ = 58800033913824. Its totient is φ = 5600003229856.

The previous prime is 21000012111997. The next prime is 21000012112069. The reversal of 21000012112020 is 2021121000012.

It is a super-3 number, since 3×21000012112020³ (a number of 41 digits) contains 333 as substring.

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 = 21000012111987 and 21000012112005.

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 7 ways as a sum of consecutive naturals, for example, 175000100874 + ... + 175000100993.

It is an arithmetic number, because the mean of its divisors is an integer number (2450001413076).

Almost surely, 2^{21000012112020} is an apocalyptic number.

21000012112020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000012112020 is an abundant number, since it is smaller than the sum of its proper divisors (37800021801804).

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

21000012112020 is a wasteful number, since it uses less digits than its factorization.

21000012112020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350000201879 (or 350000201877 counting only the distinct ones).

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

Adding to 21000012112020 its reverse (2021121000012), we get a palindrome (23021133112032).

The spelling of 21000012112020 in words is "twenty-one trillion, twelve million, one hundred twelve thousand, twenty".