216771349 has 4 divisors (see below), whose sum is σ = 219383136. Its totient is φ = 214159564.

The previous prime is 216771329. The next prime is 216771353. The reversal of 216771349 is 943177612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 216771349 - 2¹⁹ = 216247061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216771329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1305769 + ... + 1305934.

It is an arithmetic number, because the mean of its divisors is an integer number (54845784).

Almost surely, 2^216771349 is an apocalyptic number.

It is an amenable number.

216771349 is a deficient number, since it is larger than the sum of its proper divisors (2611787).

216771349 is an equidigital number, since it uses as much as digits as its factorization.

216771349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2611786.

The product of its digits is 63504, while the sum is 40.

The square root of 216771349 is about 14723.1568965355. The cubic root of 216771349 is about 600.7133635550.

The spelling of 216771349 in words is "two hundred sixteen million, seven hundred seventy-one thousand, three hundred forty-nine".