18887923 has 2 divisors, whose sum is σ = 18887924. Its totient is φ = 18887922.

The previous prime is 18887861. The next prime is 18887927. The reversal of 18887923 is 32978881.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18887923 is a prime.

It is not a weakly prime, because it can be changed into another prime (18887927) 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, 9443961 + 9443962.

It is an arithmetic number, because the mean of its divisors is an integer number (9443962).

Almost surely, 2^18887923 is an apocalyptic number.

18887923 is a deficient number, since it is larger than the sum of its proper divisors (1).

18887923 is an equidigital number, since it uses as much as digits as its factorization.

18887923 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 193536, while the sum is 46.

The square root of 18887923 is about 4346.0238149371. The cubic root of 18887923 is about 266.3144518378.

The spelling of 18887923 in words is "eighteen million, eight hundred eighty-seven thousand, nine hundred twenty-three".