216666495 has 40 divisors (see below), whose sum is σ = 392824080. Its totient is φ = 114238080.

The previous prime is 216666493. The next prime is 216666497. The reversal of 216666495 is 594666612.

It is an interprime number because it is at equal distance from previous prime (216666493) and next prime (216666497).

It is not a de Polignac number, because 216666495 - 2¹ = 216666493 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 216666495.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216666493) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 33040 + ... + 39050.

It is an arithmetic number, because the mean of its divisors is an integer number (9820602).

Almost surely, 2^216666495 is an apocalyptic number.

216666495 is a deficient number, since it is larger than the sum of its proper divisors (176157585).

216666495 is an equidigital number, since it uses as much as digits as its factorization.

216666495 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6117 (or 6108 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The square root of 216666495 is about 14719.5956126519. The cubic root of 216666495 is about 600.6164913471.

The spelling of 216666495 in words is "two hundred sixteen million, six hundred sixty-six thousand, four hundred ninety-five".