659664840 has 128 divisors (see below), whose sum is σ = 2100556800. Its totient is φ = 165369600.

The previous prime is 659664809. The next prime is 659664911. The reversal of 659664840 is 48466956.

It is a happy number.

It is a super-2 number, since 2×659664840² = 870315402264451200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 659664840.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 160815 + ... + 164865.

It is an arithmetic number, because the mean of its divisors is an integer number (16410600).

Almost surely, 2^659664840 is an apocalyptic number.

659664840 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 659664840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1050278400).

659664840 is an abundant number, since it is smaller than the sum of its proper divisors (1440891960).

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

659664840 is a wasteful number, since it uses less digits than its factorization.

659664840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4147 (or 4143 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 48.

The square root of 659664840 is about 25683.9412863369. The cubic root of 659664840 is about 870.5113653787.

The spelling of 659664840 in words is "six hundred fifty-nine million, six hundred sixty-four thousand, eight hundred forty".