664338678 has 32 divisors (see below), whose sum is σ = 1352532480. Its totient is φ = 217481760.

The previous prime is 664338677. The next prime is 664338679. The reversal of 664338678 is 876833466.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (664338677) and next prime (664338679).

It is a self number, because there is not a number n which added to its sum of digits gives 664338678.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664338671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 379401 + ... + 381147.

It is an arithmetic number, because the mean of its divisors is an integer number (42266640).

Almost surely, 2^664338678 is an apocalyptic number.

664338678 is an abundant number, since it is smaller than the sum of its proper divisors (688193802).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

664338678 is a wasteful number, since it uses less digits than its factorization.

664338678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2852.

The product of its digits is 3483648, while the sum is 51.

The square root of 664338678 is about 25774.7682433810. The cubic root of 664338678 is about 872.5624361250.

The spelling of 664338678 in words is "six hundred sixty-four million, three hundred thirty-eight thousand, six hundred seventy-eight".