21233221291 has 2 divisors, whose sum is σ = 21233221292. Its totient is φ = 21233221290.

The previous prime is 21233221277. The next prime is 21233221307. The reversal of 21233221291 is 19212233212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21233221291 is a prime.

It is not a weakly prime, because it can be changed into another prime (21233221211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10616610645 + 10616610646.

It is an arithmetic number, because the mean of its divisors is an integer number (10616610646).

Almost surely, 2^21233221291 is an apocalyptic number.

21233221291 is a deficient number, since it is larger than the sum of its proper divisors (1).

21233221291 is an equidigital number, since it uses as much as digits as its factorization.

21233221291 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 28.

The spelling of 21233221291 in words is "twenty-one billion, two hundred thirty-three million, two hundred twenty-one thousand, two hundred ninety-one".