215663466564 has 216 divisors, whose sum is σ = 688321041408. Its totient is φ = 56429654400.

The previous prime is 215663466493. The next prime is 215663466631. The reversal of 215663466564 is 465664366512.

215663466564 is a `hidden beast` number, since 2 + 15 + 6 + 6 + 3 + 4 + 66 + 564 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 215663466564.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2875339 + ... + 2949389.

It is an arithmetic number, because the mean of its divisors is an integer number (3186671488).

Almost surely, 2^215663466564 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 215663466564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (344160520704).

215663466564 is an abundant number, since it is smaller than the sum of its proper divisors (472657574844).

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

215663466564 is a wasteful number, since it uses less digits than its factorization.

215663466564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74215 (or 74203 counting only the distinct ones).

The product of its digits is 18662400, while the sum is 54.

The spelling of 215663466564 in words is "two hundred fifteen billion, six hundred sixty-three million, four hundred sixty-six thousand, five hundred sixty-four".