216660665466 has 36 divisors (see below), whose sum is σ = 546073312122. Its totient is φ = 61903047024.

The previous prime is 216660665453. The next prime is 216660665479. The reversal of 216660665466 is 664566066612.

It is an interprime number because it is at equal distance from previous prime (216660665453) and next prime (216660665479).

It can be written as a sum of positive squares in only one way, i.e., 156281855625 + 60378809841 = 395325^2 + 245721^2 .

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 122822625 + ... + 122824388.

Almost surely, 2^216660665466 is an apocalyptic number.

216660665466 is an abundant number, since it is smaller than the sum of its proper divisors (329412646656).

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

216660665466 is a wasteful number, since it uses less digits than its factorization.

216660665466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245647035 (or 245647025 counting only the distinct ones).

The product of its (nonzero) digits is 11197440, while the sum is 54.

The spelling of 216660665466 in words is "two hundred sixteen billion, six hundred sixty million, six hundred sixty-five thousand, four hundred sixty-six".