64089840 has 80 divisors (see below), whose sum is σ = 200799648. Its totient is φ = 16908288.

The previous prime is 64089829. The next prime is 64089841. The reversal of 64089840 is 4898046.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64089841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21904 + ... + 24656.

Almost surely, 2^64089840 is an apocalyptic number.

64089840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64089840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100399824).

64089840 is an abundant number, since it is smaller than the sum of its proper divisors (136709808).

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

64089840 is a wasteful number, since it uses less digits than its factorization.

64089840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2866 (or 2860 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 39.

The square root of 64089840 is about 8005.6130308678. The cubic root of 64089840 is about 400.1870791565.

The spelling of 64089840 in words is "sixty-four million, eighty-nine thousand, eight hundred forty".