216435723617 has 2 divisors, whose sum is σ = 216435723618. Its totient is φ = 216435723616.

The previous prime is 216435723611. The next prime is 216435723769. The reversal of 216435723617 is 716327534612.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 165255258256 + 51180465361 = 406516^2 + 226231^2 .

It is a cyclic number.

It is not a de Polignac number, because 216435723617 - 2¹⁶ = 216435658081 is a prime.

It is a super-2 number, since 2×216435723617² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (216435723611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108217861808 + 108217861809.

It is an arithmetic number, because the mean of its divisors is an integer number (108217861809).

Almost surely, 2^216435723617 is an apocalyptic number.

It is an amenable number.

216435723617 is a deficient number, since it is larger than the sum of its proper divisors (1).

216435723617 is an equidigital number, since it uses as much as digits as its factorization.

216435723617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1270080, while the sum is 47.

The spelling of 216435723617 in words is "two hundred sixteen billion, four hundred thirty-five million, seven hundred twenty-three thousand, six hundred seventeen".