123456791 has 2 divisors, whose sum is σ = 123456792.
Its totient is φ = 123456790.
The previous prime is 123456761. The next prime is 123456803. The reversal of 123456791 is 197654321.
It is a strong prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-123456791 is a prime.
It is a Chen prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (123456731) 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 as a sum of consecutive naturals, namely, 61728395 + 61728396.
It is an arithmetic number, because the mean of its divisors is an integer number (61728396).
Almost surely, 2123456791 is an apocalyptic number.
123456791 is a deficient number, since it is larger than the sum of its proper divisors (1).
123456791 is an equidigital number, since it uses as much as digits as its factorization.
123456791 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 45360, while the sum is 38.
The square root of 123456791 is about 11111.1111505556.
Note that the first 4 decimals coincide.
The cubic root of 123456791 is about 497.9338619070.
The spelling of 123456791 in words is "one hundred twenty-three million, four hundred fifty-six thousand, seven hundred ninety-one".