21211211102220 has 108 divisors (see below), whose sum is σ = 65449678890960. Its totient is φ = 5560452915648.

The previous prime is 21211211102201. The next prime is 21211211102233. The reversal of 21211211102220 is 2220111211212.

21211211102220 is a `hidden beast` number, since 21 + 211 + 211 + 1 + 0 + 2 + 220 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21211211102193 and 21211211102202.

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 35 ways as a sum of consecutive naturals, for example, 16299600 + ... + 17552759.

Almost surely, 2^{21211211102220} is an apocalyptic number.

21211211102220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211211102220 is an abundant number, since it is smaller than the sum of its proper divisors (44238467788740).

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

21211211102220 is a wasteful number, since it uses less digits than its factorization.

21211211102220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33852492 (or 33852428 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21211211102220 its reverse (2220111211212), we get a palindrome (23431322313432).

The spelling of 21211211102220 in words is "twenty-one trillion, two hundred eleven billion, two hundred eleven million, one hundred two thousand, two hundred twenty".