216678746 has 16 divisors (see below), whose sum is σ = 330381288. Its totient is φ = 106560000.

The previous prime is 216678713. The next prime is 216678757. The reversal of 216678746 is 647876612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 215766721 + 912025 = 14689^2 + 955^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 216678746.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56696 + ... + 60396.

Almost surely, 2^216678746 is an apocalyptic number.

216678746 is a deficient number, since it is larger than the sum of its proper divisors (113702542).

216678746 is a wasteful number, since it uses less digits than its factorization.

216678746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4177.

The product of its digits is 677376, while the sum is 47.

The square root of 216678746 is about 14720.0117527127. The cubic root of 216678746 is about 600.6278113775.

The spelling of 216678746 in words is "two hundred sixteen million, six hundred seventy-eight thousand, seven hundred forty-six".