64638287 has 4 divisors (see below), whose sum is σ = 73872336. Its totient is φ = 55404240.

The previous prime is 64638281. The next prime is 64638293. The reversal of 64638287 is 78283646.

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

It is an interprime number because it is at equal distance from previous prime (64638281) and next prime (64638293).

It is a cyclic number.

It is not a de Polignac number, because 64638287 - 2⁴ = 64638271 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64638281) 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, 4617014 + ... + 4617027.

It is an arithmetic number, because the mean of its divisors is an integer number (18468084).

Almost surely, 2^64638287 is an apocalyptic number.

64638287 is a deficient number, since it is larger than the sum of its proper divisors (9234049).

64638287 is an equidigital number, since it uses as much as digits as its factorization.

64638287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9234048.

The product of its digits is 387072, while the sum is 44.

The square root of 64638287 is about 8039.7939650217. The cubic root of 64638287 is about 401.3253682307.

The spelling of 64638287 in words is "sixty-four million, six hundred thirty-eight thousand, two hundred eighty-seven".