64439866 has 8 divisors (see below), whose sum is σ = 99272340. Its totient is φ = 31349088.

The previous prime is 64439861. The next prime is 64439873. The reversal of 64439866 is 66893446.

It can be written as a sum of positive squares in 2 ways, for example, as 63920025 + 519841 = 7995^2 + 721^2 .

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

It is not an unprimeable number, because it can be changed into a prime (64439861) 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, 435331 + ... + 435478.

Almost surely, 2^64439866 is an apocalyptic number.

64439866 is a deficient number, since it is larger than the sum of its proper divisors (34832474).

64439866 is a wasteful number, since it uses less digits than its factorization.

64439866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 870848.

The product of its digits is 746496, while the sum is 46.

The square root of 64439866 is about 8027.4445497929. Note that the first 3 decimals coincide. The cubic root of 64439866 is about 400.9142960645.

The spelling of 64439866 in words is "sixty-four million, four hundred thirty-nine thousand, eight hundred sixty-six".