21000011222120 has 64 divisors (see below), whose sum is σ = 54004549132800. Its totient is φ = 7199401144320.

The previous prime is 21000011222081. The next prime is 21000011222123. The reversal of 21000011222120 is 2122211000012.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21000011222095 and 21000011222104.

It is not an unprimeable number, because it can be changed into a prime (21000011222123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 218225 + ... + 6484415.

It is an arithmetic number, because the mean of its divisors is an integer number (843821080200).

Almost surely, 2^{21000011222120} is an apocalyptic number.

21000011222120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000011222120 is an abundant number, since it is smaller than the sum of its proper divisors (33004537910680).

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

21000011222120 is a wasteful number, since it uses less digits than its factorization.

21000011222120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6278178 (or 6278174 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21000011222120 its reverse (2122211000012), we get a palindrome (23122222222132).

The spelling of 21000011222120 in words is "twenty-one trillion, eleven million, two hundred twenty-two thousand, one hundred twenty".