216759997 has 2 divisors, whose sum is σ = 216759998. Its totient is φ = 216759996.

The previous prime is 216759971. The next prime is 216760001. The reversal of 216759997 is 799957612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173870596 + 42889401 = 13186^2 + 6549^2 .

It is a cyclic number.

It is not a de Polignac number, because 216759997 - 2²⁷ = 82542269 is a prime.

It is a super-3 number, since 3×216759997³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216759937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108379998 + 108379999.

It is an arithmetic number, because the mean of its divisors is an integer number (108379999).

Almost surely, 2^216759997 is an apocalyptic number.

It is an amenable number.

216759997 is a deficient number, since it is larger than the sum of its proper divisors (1).

216759997 is an equidigital number, since it uses as much as digits as its factorization.

216759997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2143260, while the sum is 55.

The square root of 216759997 is about 14722.7713763408. The cubic root of 216759997 is about 600.7028772104.

The spelling of 216759997 in words is "two hundred sixteen million, seven hundred fifty-nine thousand, nine hundred ninety-seven".