21621266274323 has 2 divisors, whose sum is σ = 21621266274324. Its totient is φ = 21621266274322.

The previous prime is 21621266274253. The next prime is 21621266274347. The reversal of 21621266274323 is 32347266212612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21621266274323 - 2⁸ = 21621266274067 is a prime.

It is not a weakly prime, because it can be changed into another prime (21621266274623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10810633137161 + 10810633137162.

It is an arithmetic number, because the mean of its divisors is an integer number (10810633137162).

Almost surely, 2^{21621266274323} is an apocalyptic number.

21621266274323 is a deficient number, since it is larger than the sum of its proper divisors (1).

21621266274323 is an equidigital number, since it uses as much as digits as its factorization.

21621266274323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 47.

The spelling of 21621266274323 in words is "twenty-one trillion, six hundred twenty-one billion, two hundred sixty-six million, two hundred seventy-four thousand, three hundred twenty-three".