64221864 has 64 divisors (see below), whose sum is σ = 184343040. Its totient is φ = 18264000.

The previous prime is 64221821. The next prime is 64221887. The reversal of 64221864 is 46812246.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41407 + ... + 42929.

It is an arithmetic number, because the mean of its divisors is an integer number (2880360).

Almost surely, 2^64221864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64221864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92171520).

64221864 is an abundant number, since it is smaller than the sum of its proper divisors (120121176).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64221864 is a wasteful number, since it uses less digits than its factorization.

64221864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1790 (or 1786 counting only the distinct ones).

The product of its digits is 18432, while the sum is 33.

The square root of 64221864 is about 8013.8545032962. The cubic root of 64221864 is about 400.4616835823.

The spelling of 64221864 in words is "sixty-four million, two hundred twenty-one thousand, eight hundred sixty-four".