64649664 has 84 divisors (see below), whose sum is σ = 192216024. Its totient is φ = 21544704.

The previous prime is 64649653. The next prime is 64649699. The reversal of 64649664 is 46694646.

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13474 + ... + 17630.

It is an arithmetic number, because the mean of its divisors is an integer number (2288286).

Almost surely, 2^64649664 is an apocalyptic number.

64649664 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 64649664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96108012).

64649664 is an abundant number, since it is smaller than the sum of its proper divisors (127566360).

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

64649664 is an equidigital number, since it uses as much as digits as its factorization.

64649664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4184 (or 4162 counting only the distinct ones).

The product of its digits is 746496, while the sum is 45.

The square root of 64649664 is about 8040.5014768981. The cubic root of 64649664 is about 401.3489126400.

The spelling of 64649664 in words is "sixty-four million, six hundred forty-nine thousand, six hundred sixty-four".