21201001111220 has 96 divisors (see below), whose sum is σ = 50979597177600. Its totient is φ = 7255038219264.

The previous prime is 21201001111201. The next prime is 21201001111229. The reversal of 21201001111220 is 2211110010212.

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 = 21201001111195 and 21201001111204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201001111229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 249442691 + ... + 249527669.

It is an arithmetic number, because the mean of its divisors is an integer number (531037470600).

Almost surely, 2^{21201001111220} is an apocalyptic number.

21201001111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201001111220 is an abundant number, since it is smaller than the sum of its proper divisors (29778596066380).

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

21201001111220 is a wasteful number, since it uses less digits than its factorization.

21201001111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88377 (or 88375 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21201001111220 its reverse (2211110010212), we get a palindrome (23412111121432).

The spelling of 21201001111220 in words is "twenty-one trillion, two hundred one billion, one million, one hundred eleven thousand, two hundred twenty".