216261344993 has 2 divisors, whose sum is σ = 216261344994. Its totient is φ = 216261344992.

The previous prime is 216261344903. The next prime is 216261345037. The reversal of 216261344993 is 399443162612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200196289489 + 16065055504 = 447433^2 + 126748^2 .

It is a cyclic number.

It is not a de Polignac number, because 216261344993 - 2²⁶ = 216194236129 is a prime.

It is not a weakly prime, because it can be changed into another prime (216261344903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108130672496 + 108130672497.

It is an arithmetic number, because the mean of its divisors is an integer number (108130672497).

Almost surely, 2^216261344993 is an apocalyptic number.

It is an amenable number.

216261344993 is a deficient number, since it is larger than the sum of its proper divisors (1).

216261344993 is an equidigital number, since it uses as much as digits as its factorization.

216261344993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1679616, while the sum is 50.

The spelling of 216261344993 in words is "two hundred sixteen billion, two hundred sixty-one million, three hundred forty-four thousand, nine hundred ninety-three".