7643664 has 60 divisors (see below), whose sum is σ = 24450816. Its totient is φ = 2183616.

The previous prime is 7643663. The next prime is 7643677. The reversal of 7643664 is 4663467.

7643664 is a `hidden beast` number, since 7 + 643 + 6 + 6 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a d-powerful number, because it can be written as 7⁵ + 6⁵ + 4⁸ + 3² + 6⁸ + 6⁸ + 4¹¹ .

It is not an unprimeable number, because it can be changed into a prime (7643663) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2784 + ... + 4799.

Almost surely, 2^7643664 is an apocalyptic number.

It is an amenable number.

7643664 is an abundant number, since it is smaller than the sum of its proper divisors (16807152).

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

7643664 is a wasteful number, since it uses less digits than its factorization.

7643664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7604 (or 7595 counting only the distinct ones).

The product of its digits is 72576, while the sum is 36.

The square root of 7643664 is about 2764.7177071086. The cubic root of 7643664 is about 196.9853201804.

The spelling of 7643664 in words is "seven million, six hundred forty-three thousand, six hundred sixty-four".