64806830640 has 120 divisors (see below), whose sum is σ = 218139773280. Its totient is φ = 17242371072.

The previous prime is 64806830623. The next prime is 64806830701. The reversal of 64806830640 is 4603860846.

It is a tau number, because it is divible by the number of its divisors (120).

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 213564 + ... + 418596.

It is an arithmetic number, because the mean of its divisors is an integer number (1817831444).

Almost surely, 2^64806830640 is an apocalyptic number.

64806830640 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 64806830640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109069886640).

64806830640 is an abundant number, since it is smaller than the sum of its proper divisors (153332942640).

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

64806830640 is a wasteful number, since it uses less digits than its factorization.

64806830640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205491 (or 205482 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The spelling of 64806830640 in words is "sixty-four billion, eight hundred six million, eight hundred thirty thousand, six hundred forty".