211216667 has 4 divisors (see below), whose sum is σ = 214110120. Its totient is φ = 208323216.

The previous prime is 211216651. The next prime is 211216703. The reversal of 211216667 is 766612112.

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 211216667 - 2⁴ = 211216651 is a prime.

It is a super-2 number, since 2×211216667² = 89224960837177778, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211212667) 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, 1446617 + ... + 1446762.

It is an arithmetic number, because the mean of its divisors is an integer number (53527530).

Almost surely, 2^211216667 is an apocalyptic number.

211216667 is a deficient number, since it is larger than the sum of its proper divisors (2893453).

211216667 is an equidigital number, since it uses as much as digits as its factorization.

211216667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2893452.

The product of its digits is 6048, while the sum is 32.

The square root of 211216667 is about 14533.2951184513. The cubic root of 211216667 is about 595.5378861244.

Adding to 211216667 its reverse (766612112), we get a palindrome (977828779).

The spelling of 211216667 in words is "two hundred eleven million, two hundred sixteen thousand, six hundred sixty-seven".