21226765247 has 2 divisors, whose sum is σ = 21226765248. Its totient is φ = 21226765246.

The previous prime is 21226765243. The next prime is 21226765279. The reversal of 21226765247 is 74256762212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21226765247 - 2² = 21226765243 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21226765198 and 21226765207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21226765243) 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, 10613382623 + 10613382624.

It is an arithmetic number, because the mean of its divisors is an integer number (10613382624).

Almost surely, 2^21226765247 is an apocalyptic number.

21226765247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21226765247 is an equidigital number, since it uses as much as digits as its factorization.

21226765247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 564480, while the sum is 44.

The spelling of 21226765247 in words is "twenty-one billion, two hundred twenty-six million, seven hundred sixty-five thousand, two hundred forty-seven".