21111001222000 has 80 divisors (see below), whose sum is σ = 51047407756800. Its totient is φ = 8444233939200.

The previous prime is 21111001221977. The next prime is 21111001222007. The reversal of 21111001222000 is 22210011112.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-4 number, since 4×21111001222000⁴ (a number of 54 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111001222007) 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, 174657586 + ... + 174778414.

It is an arithmetic number, because the mean of its divisors is an integer number (638092596960).

Almost surely, 2^{21111001222000} is an apocalyptic number.

21111001222000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111001222000 is an abundant number, since it is smaller than the sum of its proper divisors (29936406534800).

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

21111001222000 is a wasteful number, since it uses less digits than its factorization.

21111001222000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208211 (or 208195 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21111001222000 its reverse (22210011112), we get a palindrome (21133211233112).

The spelling of 21111001222000 in words is "twenty-one trillion, one hundred eleven billion, one million, two hundred twenty-two thousand".