819681263 has 2 divisors, whose sum is σ = 819681264. Its totient is φ = 819681262.

The previous prime is 819681253. The next prime is 819681353. The reversal of 819681263 is 362186918.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 819681263 - 2²⁰ = 818632687 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (819681253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409840631 + 409840632.

It is an arithmetic number, because the mean of its divisors is an integer number (409840632).

Almost surely, 2^819681263 is an apocalyptic number.

819681263 is a deficient number, since it is larger than the sum of its proper divisors (1).

819681263 is an equidigital number, since it uses as much as digits as its factorization.

819681263 is an evil number, because the sum of its binary digits is even.

The product of its digits is 124416, while the sum is 44.

The square root of 819681263 is about 28630.0761961962. The cubic root of 819681263 is about 935.8688723307.

The spelling of 819681263 in words is "eight hundred nineteen million, six hundred eighty-one thousand, two hundred sixty-three".