21110011311220 has 96 divisors (see below), whose sum is σ = 48401450227872. Its totient is φ = 7686681919488.

The previous prime is 21110011311217. The next prime is 21110011311239. The reversal of 21110011311220 is 2211311001112.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 5830621550224 + 15279389760996 = 2414668^2 + 3908886^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21110011311194 and 21110011311203.

It is a congruent number.

It is an unprimeable number.

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, 152776884 + ... + 152914996.

It is an arithmetic number, because the mean of its divisors is an integer number (504181773207).

Almost surely, 2^{21110011311220} is an apocalyptic number.

21110011311220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21110011311220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24200725113936).

21110011311220 is an abundant number, since it is smaller than the sum of its proper divisors (27291438916652).

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

21110011311220 is a wasteful number, since it uses less digits than its factorization.

21110011311220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146261 (or 146259 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 16.

Adding to 21110011311220 its reverse (2211311001112), we get a palindrome (23321322312332).

The spelling of 21110011311220 in words is "twenty-one trillion, one hundred ten billion, eleven million, three hundred eleven thousand, two hundred twenty".