216776407 has 2 divisors, whose sum is σ = 216776408. Its totient is φ = 216776406.

The previous prime is 216776383. The next prime is 216776411. The reversal of 216776407 is 704677612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 216776407 - 2¹⁹ = 216252119 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216776407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216776437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108388203 + 108388204.

It is an arithmetic number, because the mean of its divisors is an integer number (108388204).

Almost surely, 2^216776407 is an apocalyptic number.

216776407 is a deficient number, since it is larger than the sum of its proper divisors (1).

216776407 is an equidigital number, since it uses as much as digits as its factorization.

216776407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 98784, while the sum is 40.

The square root of 216776407 is about 14723.3286657603. The cubic root of 216776407 is about 600.7180357354.

The spelling of 216776407 in words is "two hundred sixteen million, seven hundred seventy-six thousand, four hundred seven".