216617640 has 32 divisors (see below), whose sum is σ = 649853280. Its totient is φ = 57764672.

The previous prime is 216617627. The next prime is 216617641. The reversal of 216617640 is 46716612.

It is not an unprimeable number, because it can be changed into a prime (216617641) by changing a digit.

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, 902454 + ... + 902693.

It is an arithmetic number, because the mean of its divisors is an integer number (20307915).

Almost surely, 2^216617640 is an apocalyptic number.

216617640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216617640 is an abundant number, since it is smaller than the sum of its proper divisors (433235640).

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

216617640 is a wasteful number, since it uses less digits than its factorization.

216617640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1805161 (or 1805157 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 216617640 is about 14717.9359965995. The cubic root of 216617640 is about 600.5713446583.

The spelling of 216617640 in words is "two hundred sixteen million, six hundred seventeen thousand, six hundred forty".