64638663 has 4 divisors (see below), whose sum is σ = 86184888. Its totient is φ = 43092440.

The previous prime is 64638661. The next prime is 64638697. The reversal of 64638663 is 36683646.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 64638663 - 2¹ = 64638661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64638661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10773108 + ... + 10773113.

It is an arithmetic number, because the mean of its divisors is an integer number (21546222).

Almost surely, 2^64638663 is an apocalyptic number.

64638663 is a deficient number, since it is larger than the sum of its proper divisors (21546225).

64638663 is a wasteful number, since it uses less digits than its factorization.

64638663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21546224.

The product of its digits is 373248, while the sum is 42.

The square root of 64638663 is about 8039.8173486715. The cubic root of 64638663 is about 401.3261463972.

The spelling of 64638663 in words is "sixty-four million, six hundred thirty-eight thousand, six hundred sixty-three".