216661670 has 8 divisors (see below), whose sum is σ = 389991024. Its totient is φ = 86664664.

The previous prime is 216661667. The next prime is 216661699. The reversal of 216661670 is 76166612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 216661670.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10833074 + ... + 10833093.

It is an arithmetic number, because the mean of its divisors is an integer number (48748878).

Almost surely, 2^216661670 is an apocalyptic number.

216661670 is a deficient number, since it is larger than the sum of its proper divisors (173329354).

216661670 is a wasteful number, since it uses less digits than its factorization.

216661670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21666174.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 216661670 is about 14719.4317145738. The cubic root of 216661670 is about 600.6120328880.

It can be divided in two parts, 2166 and 61670, that added together give a palindrome (63836).

The spelling of 216661670 in words is "two hundred sixteen million, six hundred sixty-one thousand, six hundred seventy".