21210304267 has 2 divisors, whose sum is σ = 21210304268. Its totient is φ = 21210304266.

The previous prime is 21210304237. The next prime is 21210304321. The reversal of 21210304267 is 76240301212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21210304267 - 2²³ = 21201915659 is a prime.

It is not a weakly prime, because it can be changed into another prime (21210304237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605152133 + 10605152134.

It is an arithmetic number, because the mean of its divisors is an integer number (10605152134).

Almost surely, 2^21210304267 is an apocalyptic number.

21210304267 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210304267 is an equidigital number, since it uses as much as digits as its factorization.

21210304267 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 28.

Adding to 21210304267 its reverse (76240301212), we get a palindrome (97450605479).

The spelling of 21210304267 in words is "twenty-one billion, two hundred ten million, three hundred four thousand, two hundred sixty-seven".