659984640 has 288 divisors, whose sum is σ = 2469282816. Its totient is φ = 147087360.

The previous prime is 659984629. The next prime is 659984653. The reversal of 659984640 is 46489956.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

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 31 ways as a sum of consecutive naturals, for example, 1155555 + ... + 1156125.

Almost surely, 2^659984640 is an apocalyptic number.

659984640 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 659984640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1234641408).

659984640 is an abundant number, since it is smaller than the sum of its proper divisors (1809298176).

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

659984640 is a wasteful number, since it uses less digits than its factorization.

659984640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 631 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 51.

The square root of 659984640 is about 25690.1662119964. The cubic root of 659984640 is about 870.6520148636.

The spelling of 659984640 in words is "six hundred fifty-nine million, nine hundred eighty-four thousand, six hundred forty".