22101220100021 has 4 divisors (see below), whose sum is σ = 22640274248844. Its totient is φ = 21562165951200.

The previous prime is 22101220099991. The next prime is 22101220100033. The reversal of 22101220100021 is 12000102210122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6564300043921 + 15536920056100 = 2562089^2 + 3941690^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22101220100021 is a prime.

It is a super-2 number, since 2×22101220100021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22101220099969 and 22101220100005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22101220100041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 269527074350 + ... + 269527074431.

It is an arithmetic number, because the mean of its divisors is an integer number (5660068562211).

Almost surely, 2^{22101220100021} is an apocalyptic number.

It is an amenable number.

22101220100021 is a deficient number, since it is larger than the sum of its proper divisors (539054148823).

22101220100021 is an equidigital number, since it uses as much as digits as its factorization.

22101220100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539054148822.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 22101220100021 its reverse (12000102210122), we get a palindrome (34101322310143).

The spelling of 22101220100021 in words is "twenty-two trillion, one hundred one billion, two hundred twenty million, one hundred thousand, twenty-one".