819917223 has 4 divisors (see below), whose sum is σ = 1093222968. Its totient is φ = 546611480.

The previous prime is 819917201. The next prime is 819917237. The reversal of 819917223 is 322719918.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 819917223 - 2⁸ = 819916967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819117223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136652868 + ... + 136652873.

It is an arithmetic number, because the mean of its divisors is an integer number (273305742).

Almost surely, 2^819917223 is an apocalyptic number.

819917223 is a deficient number, since it is larger than the sum of its proper divisors (273305745).

819917223 is a wasteful number, since it uses less digits than its factorization.

819917223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273305744.

The product of its digits is 54432, while the sum is 42.

The square root of 819917223 is about 28634.1967409599. The cubic root of 819917223 is about 935.9586659463.

The spelling of 819917223 in words is "eight hundred nineteen million, nine hundred seventeen thousand, two hundred twenty-three".