64389920 has 144 divisors (see below), whose sum is σ = 182020608. Its totient is φ = 21450240.

The previous prime is 64389911. The next prime is 64389959. The reversal of 64389920 is 2998346.

It is a happy number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 337025 + ... + 337215.

It is an arithmetic number, because the mean of its divisors is an integer number (1264032).

Almost surely, 2^64389920 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 64389920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91010304).

64389920 is an abundant number, since it is smaller than the sum of its proper divisors (117630688).

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

64389920 is a wasteful number, since it uses less digits than its factorization.

64389920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 41.

The square root of 64389920 is about 8024.3329940874. The cubic root of 64389920 is about 400.8106891810.

The spelling of 64389920 in words is "sixty-four million, three hundred eighty-nine thousand, nine hundred twenty".