306686521685664 has 240 divisors, whose sum is σ = 927291149597736. Its totient is φ = 99375388876800.

The previous prime is 306686521685659. The next prime is 306686521685671. The reversal of 306686521685664 is 466586125686603.

306686521685664 is a `hidden beast` number, since 3 + 0 + 6 + 6 + 8 + 6 + 52 + 1 + 6 + 8 + 566 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 223994924931600 + 82691596754064 = 14966460^2 + 9093492^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 306686521685592 and 306686521685601.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 24228204 + ... + 34646484.

Almost surely, 2^{306686521685664} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 306686521685664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (463645574798868).

306686521685664 is an abundant number, since it is smaller than the sum of its proper divisors (620604627912072).

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

306686521685664 is a wasteful number, since it uses less digits than its factorization.

306686521685664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10418621 (or 10418604 counting only the distinct ones).

The product of its (nonzero) digits is 1791590400, while the sum is 72.

The spelling of 306686521685664 in words is "three hundred six trillion, six hundred eighty-six billion, five hundred twenty-one million, six hundred eighty-five thousand, six hundred sixty-four".