659691581796 has 315 divisors, whose sum is σ = 1896440753501. Its totient is φ = 200701328256.

The previous prime is 659691581779. The next prime is 659691581819. The reversal of 659691581796 is 697185196956.

The square root of 659691581796 is 812214.

It is a perfect power (a square), and thus also a powerful number.

659691581796 is a `hidden beast` number, since 6 + 596 + 9 + 15 + 8 + 17 + 9 + 6 = 666.

It can be written as a sum of positive squares in 7 ways, for example, as 591382532196 + 68309049600 = 769014^2 + 261360^2 .

It is a Smith number, since the sum of its digits (72) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

Its product of digits (220449600) is a multiple of the sum of its prime factors (252).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 104 ways as a sum of consecutive naturals, for example, 7412264920 + ... + 7412265008.

Almost surely, 2^659691581796 is an apocalyptic number.

659691581796 is the 812214-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 659691581796

659691581796 is an abundant number, since it is smaller than the sum of its proper divisors (1236749171705).

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

659691581796 is an frugal number, since it uses more digits than its factorization.

659691581796 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 107 counting only the distinct ones).

The product of its digits is 220449600, while the sum is 72.

The spelling of 659691581796 in words is "six hundred fifty-nine billion, six hundred ninety-one million, five hundred eighty-one thousand, seven hundred ninety-six".