64543687 has 4 divisors (see below), whose sum is σ = 69508600. Its totient is φ = 59578776.

The previous prime is 64543669. The next prime is 64543691. The reversal of 64543687 is 78634546.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64543687 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 (64543657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2482437 + ... + 2482462.

It is an arithmetic number, because the mean of its divisors is an integer number (17377150).

Almost surely, 2^64543687 is an apocalyptic number.

64543687 is a deficient number, since it is larger than the sum of its proper divisors (4964913).

64543687 is a wasteful number, since it uses less digits than its factorization.

64543687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4964912.

The product of its digits is 483840, while the sum is 43.

The square root of 64543687 is about 8033.9085755316. The cubic root of 64543687 is about 401.1294888852.

The spelling of 64543687 in words is "sixty-four million, five hundred forty-three thousand, six hundred eighty-seven".