18220823 has 2 divisors, whose sum is σ = 18220824. Its totient is φ = 18220822.

The previous prime is 18220799. The next prime is 18220841. The reversal of 18220823 is 32802281.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18220823 - 2⁶ = 18220759 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18220792 and 18220801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18220123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9110411 + 9110412.

It is an arithmetic number, because the mean of its divisors is an integer number (9110412).

Almost surely, 2^18220823 is an apocalyptic number.

18220823 is a deficient number, since it is larger than the sum of its proper divisors (1).

18220823 is an equidigital number, since it uses as much as digits as its factorization.

18220823 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 18220823 is about 4268.5855971270. The cubic root of 18220823 is about 263.1414901753.

The spelling of 18220823 in words is "eighteen million, two hundred twenty thousand, eight hundred twenty-three".