18122791 has 2 divisors, whose sum is σ = 18122792. Its totient is φ = 18122790.

The previous prime is 18122759. The next prime is 18122809. The reversal of 18122791 is 19722181.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18122791 - 2⁵ = 18122759 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18122191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9061395 + 9061396.

It is an arithmetic number, because the mean of its divisors is an integer number (9061396).

Almost surely, 2^18122791 is an apocalyptic number.

18122791 is a deficient number, since it is larger than the sum of its proper divisors (1).

18122791 is an equidigital number, since it uses as much as digits as its factorization.

18122791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 31.

The square root of 18122791 is about 4257.0871496835. The cubic root of 18122791 is about 262.6687217652.

The spelling of 18122791 in words is "eighteen million, one hundred twenty-two thousand, seven hundred ninety-one".