664798 has 4 divisors (see below), whose sum is σ = 997200. Its totient is φ = 332398.

The previous prime is 664793. The next prime is 664799. The reversal of 664798 is 897466.

664798 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 897466 = 2 ⋅448733.

It is a self number, because there is not a number n which added to its sum of digits gives 664798.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166198 + ... + 166201.

It is an arithmetic number, because the mean of its divisors is an integer number (249300).

2⁶⁶⁴⁷⁹⁸ is an apocalyptic number.

664798 is a deficient number, since it is larger than the sum of its proper divisors (332402).

664798 is a wasteful number, since it uses less digits than its factorization.

664798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332401.

The product of its digits is 72576, while the sum is 40.

The square root of 664798 is about 815.3514579615. The cubic root of 664798 is about 87.2763485582.

The spelling of 664798 in words is "six hundred sixty-four thousand, seven hundred ninety-eight".