6656604864 has 448 divisors, whose sum is σ = 23341925376. Its totient is φ = 1624375296.

The previous prime is 6656604853. The next prime is 6656604893. The reversal of 6656604864 is 4684066566.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21682599 + ... + 21682905.

It is an arithmetic number, because the mean of its divisors is an integer number (52102512).

Almost surely, 2^6656604864 is an apocalyptic number.

6656604864 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 6656604864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11670962688).

6656604864 is an abundant number, since it is smaller than the sum of its proper divisors (16685320512).

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

6656604864 is a wasteful number, since it uses less digits than its factorization.

6656604864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 422 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 51.

The square root of 6656604864 is about 81588.0191204567. The cubic root of 6656604864 is about 1881.1247291279.

The spelling of 6656604864 in words is "six billion, six hundred fifty-six million, six hundred four thousand, eight hundred sixty-four".