21221002222051 has 2 divisors, whose sum is σ = 21221002222052. Its totient is φ = 21221002222050.

The previous prime is 21221002222039. The next prime is 21221002222127. The reversal of 21221002222051 is 15022220012212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21221002222051 - 2¹¹ = 21221002220003 is a prime.

It is not a weakly prime, because it can be changed into another prime (21221002225051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610501111025 + 10610501111026.

It is an arithmetic number, because the mean of its divisors is an integer number (10610501111026).

Almost surely, 2^{21221002222051} is an apocalyptic number.

21221002222051 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221002222051 is an equidigital number, since it uses as much as digits as its factorization.

21221002222051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 22.

Adding to 21221002222051 its reverse (15022220012212), we get a palindrome (36243222234263).

The spelling of 21221002222051 in words is "twenty-one trillion, two hundred twenty-one billion, two million, two hundred twenty-two thousand, fifty-one".