216052691 has 4 divisors (see below), whose sum is σ = 216525912. Its totient is φ = 215579472.

The previous prime is 216052679. The next prime is 216052703. The reversal of 216052691 is 196250612.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (216052679) and next prime (216052703).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216052691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216052601) 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, 235925 + ... + 236838.

It is an arithmetic number, because the mean of its divisors is an integer number (54131478).

Almost surely, 2^216052691 is an apocalyptic number.

216052691 is a deficient number, since it is larger than the sum of its proper divisors (473221).

216052691 is an equidigital number, since it uses as much as digits as its factorization.

216052691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473220.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 216052691 is about 14698.7309316145. The cubic root of 216052691 is about 600.0487839964.

The spelling of 216052691 in words is "two hundred sixteen million, fifty-two thousand, six hundred ninety-one".