64721347 has 4 divisors (see below), whose sum is σ = 64806280. Its totient is φ = 64636416.

The previous prime is 64721341. The next prime is 64721357. The reversal of 64721347 is 74312746.

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 64721347 - 2³ = 64721339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64721341) 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, 41313 + ... + 42850.

It is an arithmetic number, because the mean of its divisors is an integer number (16201570).

Almost surely, 2^64721347 is an apocalyptic number.

64721347 is a deficient number, since it is larger than the sum of its proper divisors (84933).

64721347 is an equidigital number, since it uses as much as digits as its factorization.

64721347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84932.

The product of its digits is 28224, while the sum is 34.

The square root of 64721347 is about 8044.9578619157. The cubic root of 64721347 is about 401.4971952739.

The spelling of 64721347 in words is "sixty-four million, seven hundred twenty-one thousand, three hundred forty-seven".