64536643 has 8 divisors (see below), whose sum is σ = 67461408. Its totient is φ = 61621824.

The previous prime is 64536623. The next prime is 64536653. The reversal of 64536643 is 34663546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64536643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64536623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12871 + ... + 17167.

It is an arithmetic number, because the mean of its divisors is an integer number (8432676).

Almost surely, 2^64536643 is an apocalyptic number.

64536643 is a deficient number, since it is larger than the sum of its proper divisors (2924765).

64536643 is a wasteful number, since it uses less digits than its factorization.

64536643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4973.

The product of its digits is 155520, while the sum is 37.

The square root of 64536643 is about 8033.4701717253. The cubic root of 64536643 is about 401.1148958808.

The spelling of 64536643 in words is "sixty-four million, five hundred thirty-six thousand, six hundred forty-three".