64389780 has 144 divisors (see below), whose sum is σ = 240449664. Its totient is φ = 13582080.

The previous prime is 64389769. The next prime is 64389799. The reversal of 64389780 is 8798346.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14415 + ... + 18345.

Almost surely, 2^64389780 is an apocalyptic number.

64389780 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

64389780 is the 6552-nd pentagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64389780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120224832).

64389780 is an abundant number, since it is smaller than the sum of its proper divisors (176059884).

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

64389780 is a wasteful number, since it uses less digits than its factorization.

64389780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3966 (or 3961 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 64389780 is about 8024.3242706162. The cubic root of 64389780 is about 400.8103986928.

The spelling of 64389780 in words is "sixty-four million, three hundred eighty-nine thousand, seven hundred eighty".