216512369 has 2 divisors, whose sum is σ = 216512370. Its totient is φ = 216512368.

The previous prime is 216512333. The next prime is 216512447. The reversal of 216512369 is 963215612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216472369 + 40000 = 14713^2 + 200^2 .

It is a cyclic number.

It is not a de Polignac number, because 216512369 - 2¹⁶ = 216446833 is a prime.

It is a super-2 number, since 2×216512369² = 93755211859984322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (216512069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108256184 + 108256185.

It is an arithmetic number, because the mean of its divisors is an integer number (108256185).

Almost surely, 2^216512369 is an apocalyptic number.

It is an amenable number.

216512369 is a deficient number, since it is larger than the sum of its proper divisors (1).

216512369 is an equidigital number, since it uses as much as digits as its factorization.

216512369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19440, while the sum is 35.

The square root of 216512369 is about 14714.3592792891. The cubic root of 216512369 is about 600.4740411171.

The spelling of 216512369 in words is "two hundred sixteen million, five hundred twelve thousand, three hundred sixty-nine".