677664 has 72 divisors (see below), whose sum is σ = 2086812. Its totient is φ = 207360.

The previous prime is 677657. The next prime is 677681. The reversal of 677664 is 466776.

It can be written as a sum of positive squares in 2 ways, for example, as 501264 + 176400 = 708^2 + 420^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

677664 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 11 ways as a sum of consecutive naturals, for example, 3654 + ... + 3834.

2⁶⁷⁷⁶⁶⁴ 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 677664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1043406).

677664 is an abundant number, since it is smaller than the sum of its proper divisors (1409148).

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

677664 is a wasteful number, since it uses less digits than its factorization.

677664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210 (or 199 counting only the distinct ones).

The product of its digits is 42336, while the sum is 36.

The square root of 677664 is about 823.2034985348. The cubic root of 677664 is about 87.8357818951.

The spelling of 677664 in words is "six hundred seventy-seven thousand, six hundred sixty-four".