819222397 has 4 divisors (see below), whose sum is σ = 936254176. Its totient is φ = 702190620.

The previous prime is 819222379. The next prime is 819222419. The reversal of 819222397 is 793222918.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 793222918 = 2 ⋅396611459.

It is a cyclic number.

It is not a de Polignac number, because 819222397 - 2¹⁹ = 818698109 is a prime.

It is a super-2 number, since 2×819222397² = 1342250671492851218, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819222307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58515879 + ... + 58515892.

It is an arithmetic number, because the mean of its divisors is an integer number (234063544).

Almost surely, 2^819222397 is an apocalyptic number.

It is an amenable number.

819222397 is a deficient number, since it is larger than the sum of its proper divisors (117031779).

819222397 is a wasteful number, since it uses less digits than its factorization.

819222397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117031778.

The product of its digits is 108864, while the sum is 43.

The square root of 819222397 is about 28622.0613688113. The cubic root of 819222397 is about 935.6942033933.

The spelling of 819222397 in words is "eight hundred nineteen million, two hundred twenty-two thousand, three hundred ninety-seven".