21220000022221 has 48 divisors (see below), whose sum is σ = 28931376555648. Its totient is φ = 15112015776000.

The previous prime is 21220000022209. The next prime is 21220000022239. The reversal of 21220000022221 is 12222000002212.

It is not a de Polignac number, because 21220000022221 - 2⁷ = 21220000022093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21220000022195 and 21220000022204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220000022521) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6758346 + ... + 9386971.

It is an arithmetic number, because the mean of its divisors is an integer number (602737011576).

Almost surely, 2^{21220000022221} is an apocalyptic number.

It is an amenable number.

21220000022221 is a deficient number, since it is larger than the sum of its proper divisors (7711376533427).

21220000022221 is a wasteful number, since it uses less digits than its factorization.

21220000022221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16145462 (or 16145449 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21220000022221 its reverse (12222000002212), we get a palindrome (33442000024433).

The spelling of 21220000022221 in words is "twenty-one trillion, two hundred twenty billion, twenty-two thousand, two hundred twenty-one".