73563610781 has 2 divisors, whose sum is σ = 73563610782. Its totient is φ = 73563610780.

The previous prime is 73563610733. The next prime is 73563610819. The reversal of 73563610781 is 18701636537.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73500089881 + 63520900 = 271109^2 + 7970^2 .

It is an emirp because it is prime and its reverse (18701636537) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73563610781 is a prime.

It is a super-2 number, since 2×73563610781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73563610381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36781805390 + 36781805391.

It is an arithmetic number, because the mean of its divisors is an integer number (36781805391).

Almost surely, 2^73563610781 is an apocalyptic number.

It is an amenable number.

73563610781 is a deficient number, since it is larger than the sum of its proper divisors (1).

73563610781 is an equidigital number, since it uses as much as digits as its factorization.

73563610781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 635040, while the sum is 47.

The spelling of 73563610781 in words is "seventy-three billion, five hundred sixty-three million, six hundred ten thousand, seven hundred eighty-one".