216406555 has 8 divisors (see below), whose sum is σ = 268642800. Its totient is φ = 167155296.

The previous prime is 216406511. The next prime is 216406571. The reversal of 216406555 is 555604612.

216406555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 216406555 - 2¹⁹ = 215882267 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216406555.

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, 746085 + ... + 746374.

It is an arithmetic number, because the mean of its divisors is an integer number (33580350).

Almost surely, 2^216406555 is an apocalyptic number.

216406555 is a deficient number, since it is larger than the sum of its proper divisors (52236245).

216406555 is a wasteful number, since it uses less digits than its factorization.

216406555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1492493.

The product of its (nonzero) digits is 36000, while the sum is 34.

The square root of 216406555 is about 14710.7632364878. The cubic root of 216406555 is about 600.3762038832.

The spelling of 216406555 in words is "two hundred sixteen million, four hundred six thousand, five hundred fifty-five".