216564553 has 2 divisors, whose sum is σ = 216564554. Its totient is φ = 216564552.

The previous prime is 216564533. The next prime is 216564559. The reversal of 216564553 is 355465612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 141776649 + 74787904 = 11907^2 + 8648^2 .

It is a cyclic number.

It is not a de Polignac number, because 216564553 - 2⁵ = 216564521 is a prime.

It is not a weakly prime, because it can be changed into another prime (216564559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108282276 + 108282277.

It is an arithmetic number, because the mean of its divisors is an integer number (108282277).

Almost surely, 2^216564553 is an apocalyptic number.

It is an amenable number.

216564553 is a deficient number, since it is larger than the sum of its proper divisors (1).

216564553 is an equidigital number, since it uses as much as digits as its factorization.

216564553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108000, while the sum is 37.

The square root of 216564553 is about 14716.1324063084. The cubic root of 216564553 is about 600.5222795009.

The spelling of 216564553 in words is "two hundred sixteen million, five hundred sixty-four thousand, five hundred fifty-three".