22121000001 has 6 divisors (see below), whose sum is σ = 31952555570. Its totient is φ = 14747333328.

The previous prime is 22120999969. The next prime is 22121000009. The reversal of 22121000001 is 10000012122.

It can be written as a sum of positive squares in only one way, i.e., 14231297025 + 7889702976 = 119295^2 + 88824^2 .

It is not a de Polignac number, because 22121000001 - 2⁵ = 22120999969 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: 2457888889 = 22121000001 / (2 + 2 + 1 + 2 + 1 + 0 + 0 + 0 + 0 + 0 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22121000009) 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, 1228944436 + ... + 1228944453.

Almost surely, 2^22121000001 is an apocalyptic number.

It is an amenable number.

22121000001 is a deficient number, since it is larger than the sum of its proper divisors (9831555569).

22121000001 is a wasteful number, since it uses less digits than its factorization.

22121000001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2457888895 (or 2457888892 counting only the distinct ones).

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

Adding to 22121000001 its reverse (10000012122), we get a palindrome (32121012123).

The spelling of 22121000001 in words is "twenty-two billion, one hundred twenty-one million, one", and thus it is an aban number.