123782941561 has 2 divisors, whose sum is σ = 123782941562. Its totient is φ = 123782941560.

The previous prime is 123782941459. The next prime is 123782941589. The reversal of 123782941561 is 165149287321.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116506851561 + 7276090000 = 341331^2 + 85300^2 .

It is an emirp because it is prime and its reverse (165149287321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123782941561 - 2¹¹ = 123782939513 is a prime.

It is a super-2 number, since 2×123782941561² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (123782941361) 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, 61891470780 + 61891470781.

It is an arithmetic number, because the mean of its divisors is an integer number (61891470781).

Almost surely, 2^123782941561 is an apocalyptic number.

It is an amenable number.

123782941561 is a deficient number, since it is larger than the sum of its proper divisors (1).

123782941561 is an equidigital number, since it uses as much as digits as its factorization.

123782941561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 725760, while the sum is 49.

The spelling of 123782941561 in words is "one hundred twenty-three billion, seven hundred eighty-two million, nine hundred forty-one thousand, five hundred sixty-one".