216913569 has 4 divisors (see below), whose sum is σ = 289218096. Its totient is φ = 144609044.

The previous prime is 216913553. The next prime is 216913589. The reversal of 216913569 is 965319612.

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 216913569 - 2⁴ = 216913553 is a prime.

It is a super-2 number, since 2×216913569² = 94102992832635522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 216913569.

It is not an unprimeable number, because it can be changed into a prime (216913589) 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, 36152259 + ... + 36152264.

It is an arithmetic number, because the mean of its divisors is an integer number (72304524).

Almost surely, 2^216913569 is an apocalyptic number.

It is an amenable number.

216913569 is a deficient number, since it is larger than the sum of its proper divisors (72304527).

216913569 is an equidigital number, since it uses as much as digits as its factorization.

216913569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72304526.

The product of its digits is 87480, while the sum is 42.

The square root of 216913569 is about 14727.9859111828. The cubic root of 216913569 is about 600.8447074464.

The spelling of 216913569 in words is "two hundred sixteen million, nine hundred thirteen thousand, five hundred sixty-nine".