6644251264 has 64 divisors (see below), whose sum is σ = 15228028800. Its totient is φ = 2828620800.

The previous prime is 6644251259. The next prime is 6644251267. The reversal of 6644251264 is 4621524466.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (6644251267) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 110742 + ... + 159850.

It is an arithmetic number, because the mean of its divisors is an integer number (237937950).

Almost surely, 2^6644251264 is an apocalyptic number.

6644251264 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 6644251264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7614014400).

6644251264 is an abundant number, since it is smaller than the sum of its proper divisors (8583777536).

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

6644251264 is a wasteful number, since it uses less digits than its factorization.

6644251264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49281 (or 49269 counting only the distinct ones).

The product of its digits is 276480, while the sum is 40.

The square root of 6644251264 is about 81512.2767685948. The cubic root of 6644251264 is about 1879.9603190659.

The spelling of 6644251264 in words is "six billion, six hundred forty-four million, two hundred fifty-one thousand, two hundred sixty-four".