666834321 has 4 divisors (see below), whose sum is σ = 889112432. Its totient is φ = 444556212.

The previous prime is 666834307. The next prime is 666834349. The reversal of 666834321 is 123438666.

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.

It is not a de Polignac number, because 666834321 - 2¹⁷ = 666703249 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666834321.

It is not an unprimeable number, because it can be changed into a prime (666834121) 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, 111139051 + ... + 111139056.

It is an arithmetic number, because the mean of its divisors is an integer number (222278108).

Almost surely, 2^666834321 is an apocalyptic number.

It is an amenable number.

666834321 is a deficient number, since it is larger than the sum of its proper divisors (222278111).

666834321 is a wasteful number, since it uses less digits than its factorization.

666834321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222278110.

The product of its digits is 124416, while the sum is 39.

The square root of 666834321 is about 25823.1353828306. The cubic root of 666834321 is about 873.6536883737.

The spelling of 666834321 in words is "six hundred sixty-six million, eight hundred thirty-four thousand, three hundred twenty-one".