22001000121 has 6 divisors (see below), whose sum is σ = 31779222410. Its totient is φ = 14667333408.

The previous prime is 22001000107. The next prime is 22001000123. The reversal of 22001000121 is 12100010022.

It can be written as a sum of positive squares in only one way, i.e., 14051494521 + 7949505600 = 118539^2 + 89160^2 .

It is not a de Polignac number, because 22001000121 - 2⁹ = 22000999609 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 2444555569 = 22001000121 / (2 + 2 + 0 + 0 + 1 + 0 + 0 + 0 + 1 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22001000123) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1222277776 + ... + 1222277793.

Almost surely, 2^22001000121 is an apocalyptic number.

It is an amenable number.

22001000121 is a deficient number, since it is larger than the sum of its proper divisors (9778222289).

22001000121 is a wasteful number, since it uses less digits than its factorization.

22001000121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2444555575 (or 2444555572 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 22001000121 its reverse (12100010022), we get a palindrome (34101010143).

Subtracting from 22001000121 its reverse (12100010022), we obtain a palindrome (9900990099).

It can be divided in two parts, 220010001 and 21, that added together give a palindrome (220010022).

The spelling of 22001000121 in words is "twenty-two billion, one million, one hundred twenty-one", and thus it is an aban number.