22121211251 has 2 divisors, whose sum is σ = 22121211252. Its totient is φ = 22121211250.

The previous prime is 22121211221. The next prime is 22121211253. The reversal of 22121211251 is 15211212122.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22121211251 is a prime.

It is a super-2 number, since 2×22121211251² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 22121211253, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (22121211253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11060605625 + 11060605626.

It is an arithmetic number, because the mean of its divisors is an integer number (11060605626).

Almost surely, 2^22121211251 is an apocalyptic number.

22121211251 is a deficient number, since it is larger than the sum of its proper divisors (1).

22121211251 is an equidigital number, since it uses as much as digits as its factorization.

22121211251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 160, while the sum is 20.

Adding to 22121211251 its reverse (15211212122), we get a palindrome (37332423373).

The spelling of 22121211251 in words is "twenty-two billion, one hundred twenty-one million, two hundred eleven thousand, two hundred fifty-one".