216638742 has 16 divisors (see below), whose sum is σ = 439213680. Its totient is φ = 71223552.

The previous prime is 216638713. The next prime is 216638753. The reversal of 216638742 is 247836612.

It is a happy number.

216638742 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 216638742.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 246867 + ... + 247742.

It is an arithmetic number, because the mean of its divisors is an integer number (27450855).

Almost surely, 2^216638742 is an apocalyptic number.

216638742 is an abundant number, since it is smaller than the sum of its proper divisors (222574938).

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

216638742 is a wasteful number, since it uses less digits than its factorization.

216638742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 494687.

The product of its digits is 96768, while the sum is 39.

The square root of 216638742 is about 14718.6528595521. The cubic root of 216638742 is about 600.5908457556.

The spelling of 216638742 in words is "two hundred sixteen million, six hundred thirty-eight thousand, seven hundred forty-two".