667505664 has 176 divisors, whose sum is σ = 2259888000. Its totient is φ = 190660608.

The previous prime is 667505651. The next prime is 667505669. The reversal of 667505664 is 466505766.

It is a super-2 number, since 2×667505664² = 891127622944161792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667505669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 191812 + ... + 195260.

Almost surely, 2^667505664 is an apocalyptic number.

667505664 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 667505664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1129944000).

667505664 is an abundant number, since it is smaller than the sum of its proper divisors (1592382336).

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

667505664 is a wasteful number, since it uses less digits than its factorization.

667505664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3485 (or 3461 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 45.

The square root of 667505664 is about 25836.1309796959. The cubic root of 667505664 is about 873.9467769519.

The spelling of 667505664 in words is "six hundred sixty-seven million, five hundred five thousand, six hundred sixty-four".