659999340 has 720 divisors, whose sum is σ = 2876655936. Its totient is φ = 123171840.

The previous prime is 659999309. The next prime is 659999357. The reversal of 659999340 is 43999956.

659999340 is a `hidden beast` number, since 6 + 599 + 9 + 9 + 3 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 17837802 + ... + 17837838.

Almost surely, 2^659999340 is an apocalyptic number.

659999340 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 659999340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1438327968).

659999340 is an abundant number, since it is smaller than the sum of its proper divisors (2216656596).

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

659999340 is a wasteful number, since it uses less digits than its factorization.

659999340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 2361960, while the sum is 54.

The square root of 659999340 is about 25690.4523120945. The cubic root of 659999340 is about 870.6584788977.

659999340 divided by its reverse (43999956) gives a triangular number (15 = T₅).

It can be divided in two parts, 659 and 999340, that added together give a palindrome (999999).

The spelling of 659999340 in words is "six hundred fifty-nine million, nine hundred ninety-nine thousand, three hundred forty".