16863136781 has 2 divisors, whose sum is σ = 16863136782. Its totient is φ = 16863136780.

The previous prime is 16863136777. The next prime is 16863136811. The reversal of 16863136781 is 18763136861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9267142756 + 7595994025 = 96266^2 + 87155^2 .

It is a cyclic number.

It is not a de Polignac number, because 16863136781 - 2² = 16863136777 is a prime.

It is a super-2 number, since 2×16863136781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16863136751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8431568390 + 8431568391.

It is an arithmetic number, because the mean of its divisors is an integer number (8431568391).

Almost surely, 2^16863136781 is an apocalyptic number.

It is an amenable number.

16863136781 is a deficient number, since it is larger than the sum of its proper divisors (1).

16863136781 is an equidigital number, since it uses as much as digits as its factorization.

16863136781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 870912, while the sum is 50.

The spelling of 16863136781 in words is "sixteen billion, eight hundred sixty-three million, one hundred thirty-six thousand, seven hundred eighty-one".