216203551 has 2 divisors, whose sum is σ = 216203552. Its totient is φ = 216203550.

The previous prime is 216203521. The next prime is 216203593. The reversal of 216203551 is 155302612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 216203551 - 2⁷ = 216203423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216203521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108101775 + 108101776.

It is an arithmetic number, because the mean of its divisors is an integer number (108101776).

Almost surely, 2^216203551 is an apocalyptic number.

216203551 is a deficient number, since it is larger than the sum of its proper divisors (1).

216203551 is an equidigital number, since it uses as much as digits as its factorization.

216203551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 216203551 is about 14703.8617716571. The cubic root of 216203551 is about 600.1884139756.

The spelling of 216203551 in words is "two hundred sixteen million, two hundred three thousand, five hundred fifty-one".