12641664 has 64 divisors (see below), whose sum is σ = 38384640. Its totient is φ = 3611136.

The previous prime is 12641663. The next prime is 12641677. The reversal of 12641664 is 46614621.

12641664 = T₁₈₉₇ + T₁₈₉₈ + ... + T₁₉₀₃.

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

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12641663) 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, 337 + ... + 5039.

It is an arithmetic number, because the mean of its divisors is an integer number (599760).

Almost surely, 2^12641664 is an apocalyptic number.

12641664 is a gapful number since it is divisible by the number (14) 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 12641664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19192320).

12641664 is an abundant number, since it is smaller than the sum of its proper divisors (25742976).

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

12641664 is an equidigital number, since it uses as much as digits as its factorization.

12641664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4727 (or 4715 counting only the distinct ones).

The product of its digits is 6912, while the sum is 30.

The square root of 12641664 is about 3555.5117775083. The cubic root of 12641664 is about 232.9528784101.

The spelling of 12641664 in words is "twelve million, six hundred forty-one thousand, six hundred sixty-four".