64478643 has 4 divisors (see below), whose sum is σ = 85971528. Its totient is φ = 42985760.

The previous prime is 64478641. The next prime is 64478663. The reversal of 64478643 is 34687446.

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 64478643 - 2¹ = 64478641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 64478595 and 64478604.

It is not an unprimeable number, because it can be changed into a prime (64478641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10746438 + ... + 10746443.

It is an arithmetic number, because the mean of its divisors is an integer number (21492882).

Almost surely, 2^64478643 is an apocalyptic number.

64478643 is a deficient number, since it is larger than the sum of its proper divisors (21492885).

64478643 is a wasteful number, since it uses less digits than its factorization.

64478643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21492884.

The product of its digits is 387072, while the sum is 42.

The square root of 64478643 is about 8029.8594632783. The cubic root of 64478643 is about 400.9946973095.

The spelling of 64478643 in words is "sixty-four million, four hundred seventy-eight thousand, six hundred forty-three".