216510661201673 has 2 divisors, whose sum is σ = 216510661201674. Its totient is φ = 216510661201672.

The previous prime is 216510661201649. The next prime is 216510661201727. The reversal of 216510661201673 is 376102166015612.

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., 148819431510649 + 67691229691024 = 12199157^2 + 8227468^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216510661201673 is a prime.

It is a super-2 number, since 2×216510661201673² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (216510661201603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108255330600836 + 108255330600837.

It is an arithmetic number, because the mean of its divisors is an integer number (108255330600837).

Almost surely, 2^{216510661201673} is an apocalyptic number.

It is an amenable number.

216510661201673 is a deficient number, since it is larger than the sum of its proper divisors (1).

216510661201673 is an equidigital number, since it uses as much as digits as its factorization.

216510661201673 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 544320, while the sum is 47.

The spelling of 216510661201673 in words is "two hundred sixteen trillion, five hundred ten billion, six hundred sixty-one million, two hundred one thousand, six hundred seventy-three".