216233291 has 4 divisors (see below), whose sum is σ = 222077472. Its totient is φ = 210389112.

The previous prime is 216233263. The next prime is 216233317. The reversal of 216233291 is 192332612.

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 216233291 - 2¹⁰ = 216232267 is a prime.

It is a super-2 number, since 2×216233291² = 93513672273381362, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216233231) 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, 2922035 + ... + 2922108.

It is an arithmetic number, because the mean of its divisors is an integer number (55519368).

Almost surely, 2^216233291 is an apocalyptic number.

216233291 is a deficient number, since it is larger than the sum of its proper divisors (5844181).

216233291 is an equidigital number, since it uses as much as digits as its factorization.

216233291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5844180.

The product of its digits is 3888, while the sum is 29.

The square root of 216233291 is about 14704.8730358341. The cubic root of 216233291 is about 600.2159324645.

It can be divided in two parts, 2162 and 33291, that added together give a palindrome (35453).

The spelling of 216233291 in words is "two hundred sixteen million, two hundred thirty-three thousand, two hundred ninety-one".