216657011 has 4 divisors (see below), whose sum is σ = 218644800. Its totient is φ = 214669224.

The previous prime is 216656977. The next prime is 216657031. The reversal of 216657011 is 110756612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216657011 - 2¹⁰ = 216655987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216657031) 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 3 ways as a sum of consecutive naturals, for example, 993731 + ... + 993948.

It is an arithmetic number, because the mean of its divisors is an integer number (54661200).

Almost surely, 2^216657011 is an apocalyptic number.

216657011 is a deficient number, since it is larger than the sum of its proper divisors (1987789).

216657011 is a wasteful number, since it uses less digits than its factorization.

216657011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1987788.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 216657011 is about 14719.2734535370. The cubic root of 216657011 is about 600.6077277556.

The spelling of 216657011 in words is "two hundred sixteen million, six hundred fifty-seven thousand, eleven".