123550505761 has 4 divisors (see below), whose sum is σ = 123551617024. Its totient is φ = 123549394500.

The previous prime is 123550505717. The next prime is 123550505777. The reversal of 123550505761 is 167505055321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 167505055321 = 11119 ⋅15064759.

It is a cyclic number.

It is not a de Polignac number, because 123550505761 - 2¹⁵ = 123550472993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123550505161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 367665 + ... + 618286.

It is an arithmetic number, because the mean of its divisors is an integer number (30887904256).

Almost surely, 2^123550505761 is an apocalyptic number.

It is an amenable number.

123550505761 is a deficient number, since it is larger than the sum of its proper divisors (1111263).

123550505761 is an equidigital number, since it uses as much as digits as its factorization.

123550505761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1111262.

The product of its (nonzero) digits is 157500, while the sum is 40.

The spelling of 123550505761 in words is "one hundred twenty-three billion, five hundred fifty million, five hundred five thousand, seven hundred sixty-one".