664123342 has 4 divisors (see below), whose sum is σ = 996185016. Its totient is φ = 332061670.

The previous prime is 664123331. The next prime is 664123357. The reversal of 664123342 is 243321466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 243321466 = 2 ⋅121660733.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166030834 + ... + 166030837.

It is an arithmetic number, because the mean of its divisors is an integer number (249046254).

Almost surely, 2^664123342 is an apocalyptic number.

664123342 is a deficient number, since it is larger than the sum of its proper divisors (332061674).

664123342 is a wasteful number, since it uses less digits than its factorization.

664123342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332061673.

The product of its digits is 20736, while the sum is 31.

The square root of 664123342 is about 25770.5906412717. The cubic root of 664123342 is about 872.4681496735.

The spelling of 664123342 in words is "six hundred sixty-four million, one hundred twenty-three thousand, three hundred forty-two".