21225102251 has 2 divisors, whose sum is σ = 21225102252. Its totient is φ = 21225102250.

The previous prime is 21225102229. The next prime is 21225102253. The reversal of 21225102251 is 15220152212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21225102251 - 2²² = 21220907947 is a prime.

Together with 21225102253, 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 (21225102253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612551125 + 10612551126.

It is an arithmetic number, because the mean of its divisors is an integer number (10612551126).

Almost surely, 2^21225102251 is an apocalyptic number.

21225102251 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225102251 is an equidigital number, since it uses as much as digits as its factorization.

21225102251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 800, while the sum is 23.

Adding to 21225102251 its reverse (15220152212), we get a palindrome (36445254463).

The spelling of 21225102251 in words is "twenty-one billion, two hundred twenty-five million, one hundred two thousand, two hundred fifty-one".