216261089 has 4 divisors (see below), whose sum is σ = 235921200. Its totient is φ = 196600980.

The previous prime is 216261037. The next prime is 216261119. The reversal of 216261089 is 980162612.

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 216261089 - 2²⁰ = 215212513 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (216261389) 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, 9830039 + ... + 9830060.

It is an arithmetic number, because the mean of its divisors is an integer number (58980300).

Almost surely, 2^216261089 is an apocalyptic number.

It is an amenable number.

216261089 is a deficient number, since it is larger than the sum of its proper divisors (19660111).

216261089 is a wasteful number, since it uses less digits than its factorization.

216261089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19660110.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 216261089 is about 14705.8182023307. The cubic root of 216261089 is about 600.2416517351.

The spelling of 216261089 in words is "two hundred sixteen million, two hundred sixty-one thousand, eighty-nine".