21204347963 has 2 divisors, whose sum is σ = 21204347964. Its totient is φ = 21204347962.

The previous prime is 21204347951. The next prime is 21204347971. The reversal of 21204347963 is 36974340212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21204347963 - 2¹⁰ = 21204346939 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21204347963.

It is not a weakly prime, because it can be changed into another prime (21204347903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10602173981 + 10602173982.

It is an arithmetic number, because the mean of its divisors is an integer number (10602173982).

Almost surely, 2^21204347963 is an apocalyptic number.

21204347963 is a deficient number, since it is larger than the sum of its proper divisors (1).

21204347963 is an equidigital number, since it uses as much as digits as its factorization.

21204347963 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 41.

The spelling of 21204347963 in words is "twenty-one billion, two hundred four million, three hundred forty-seven thousand, nine hundred sixty-three".