123991195085 has 4 divisors (see below), whose sum is σ = 148789434108. Its totient is φ = 99192956064.

The previous prime is 123991195073. The next prime is 123991195099. The reversal of 123991195085 is 580591199321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 28150799524 + 95840395561 = 167782^2 + 309581^2 .

It is a cyclic number.

It is not a de Polignac number, because 123991195085 - 2⁸ = 123991194829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12399119504 + ... + 12399119513.

It is an arithmetic number, because the mean of its divisors is an integer number (37197358527).

Almost surely, 2^123991195085 is an apocalyptic number.

It is an amenable number.

123991195085 is a deficient number, since it is larger than the sum of its proper divisors (24798239023).

123991195085 is an equidigital number, since it uses as much as digits as its factorization.

123991195085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24798239022.

The product of its (nonzero) digits is 874800, while the sum is 53.

The spelling of 123991195085 in words is "one hundred twenty-three billion, nine hundred ninety-one million, one hundred ninety-five thousand, eighty-five".