664888 has 32 divisors (see below), whose sum is σ = 1474560. Its totient is φ = 275040.

The previous prime is 664879. The next prime is 664891. The reversal of 664888 is 888466.

It is a happy number.

664888 is a modest number, since divided by 888 gives 664 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 664888.

It is a congruent number.

It is an unprimeable number.

664888 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1545 + ... + 1927.

It is an arithmetic number, because the mean of its divisors is an integer number (46080).

2⁶⁶⁴⁸⁸⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (737280).

664888 is an abundant number, since it is smaller than the sum of its proper divisors (809672).

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

664888 is a wasteful number, since it uses less digits than its factorization.

664888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 423 counting only the distinct ones).

The product of its digits is 73728, while the sum is 40.

The square root of 664888 is about 815.4066470173. The cubic root of 664888 is about 87.2802868557.

The spelling of 664888 in words is "six hundred sixty-four thousand, eight hundred eighty-eight".