21101220111000 has 64 divisors (see below), whose sum is σ = 65835806755680. Its totient is φ = 5626992028800.

The previous prime is 21101220110951. The next prime is 21101220111001. The reversal of 21101220111000 is 11102210112.

It is a super-2 number, since 2×21101220111000² (a number of 27 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101220111001) 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, 3516867019 + ... + 3516873018.

Almost surely, 2^{21101220111000} is an apocalyptic number.

21101220111000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21101220111000 is an abundant number, since it is smaller than the sum of its proper divisors (44734586644680).

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

21101220111000 is a wasteful number, since it uses less digits than its factorization.

21101220111000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7033740061 (or 7033740047 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21101220111000 its reverse (11102210112), we get a palindrome (21112322321112).

The spelling of 21101220111000 in words is "twenty-one trillion, one hundred one billion, two hundred twenty million, one hundred eleven thousand".