18391441 has 2 divisors, whose sum is σ = 18391442. Its totient is φ = 18391440.

The previous prime is 18391409. The next prime is 18391447. The reversal of 18391441 is 14419381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16646400 + 1745041 = 4080^2 + 1321^2 .

It is a cyclic number.

It is not a de Polignac number, because 18391441 - 2⁵ = 18391409 is a prime.

It is not a weakly prime, because it can be changed into another prime (18391447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9195720 + 9195721.

It is an arithmetic number, because the mean of its divisors is an integer number (9195721).

Almost surely, 2^18391441 is an apocalyptic number.

It is an amenable number.

18391441 is a deficient number, since it is larger than the sum of its proper divisors (1).

18391441 is an equidigital number, since it uses as much as digits as its factorization.

18391441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 31.

The square root of 18391441 is about 4288.5243382777. The cubic root of 18391441 is about 263.9602834728.

The spelling of 18391441 in words is "eighteen million, three hundred ninety-one thousand, four hundred forty-one".