216905541 has 8 divisors (see below), whose sum is σ = 289289184. Its totient is φ = 144562800.

The previous prime is 216905527. The next prime is 216905573. The reversal of 216905541 is 145509612.

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

It is not a de Polignac number, because 216905541 - 2⁵ = 216905509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216905041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5691 + ... + 21591.

It is an arithmetic number, because the mean of its divisors is an integer number (36161148).

Almost surely, 2^216905541 is an apocalyptic number.

It is an amenable number.

216905541 is a deficient number, since it is larger than the sum of its proper divisors (72383643).

216905541 is a wasteful number, since it uses less digits than its factorization.

216905541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20451.

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 216905541 is about 14727.7133663037. The cubic root of 216905541 is about 600.8372949074.

The spelling of 216905541 in words is "two hundred sixteen million, nine hundred five thousand, five hundred forty-one".