215686417968 has 240 divisors, whose sum is σ = 717223291200. Its totient is φ = 60461227008.

The previous prime is 215686417963. The next prime is 215686418033. The reversal of 215686417968 is 869714686512.

215686417968 is a `hidden beast` number, since 2 + 1 + 56 + 86 + 417 + 96 + 8 = 666.

215686417968 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (215686417963) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 2576580 + ... + 2658972.

It is an arithmetic number, because the mean of its divisors is an integer number (2988430380).

Almost surely, 2^215686417968 is an apocalyptic number.

215686417968 is a gapful number since it is divisible by the number (28) 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 215686417968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (358611645600).

215686417968 is an abundant number, since it is smaller than the sum of its proper divisors (501536873232).

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

215686417968 is a wasteful number, since it uses less digits than its factorization.

215686417968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82481 (or 82458 counting only the distinct ones).

The product of its digits is 34836480, while the sum is 63.

The spelling of 215686417968 in words is "two hundred fifteen billion, six hundred eighty-six million, four hundred seventeen thousand, nine hundred sixty-eight".