6504689664 has 208 divisors, whose sum is σ = 21026624640. Its totient is φ = 1970749440.

The previous prime is 6504689591. The next prime is 6504689687. The reversal of 6504689664 is 4669864056.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 6504689664.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1213839 + ... + 1219185.

Almost surely, 2^6504689664 is an apocalyptic number.

6504689664 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 6504689664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10513312320).

6504689664 is an abundant number, since it is smaller than the sum of its proper divisors (14521934976).

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

6504689664 is a wasteful number, since it uses less digits than its factorization.

6504689664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5391 (or 5363 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 54.

The square root of 6504689664 is about 80651.6563004133. The cubic root of 6504689664 is about 1866.7042967471.

The spelling of 6504689664 in words is "six billion, five hundred four million, six hundred eighty-nine thousand, six hundred sixty-four".