18240961 has 2 divisors, whose sum is σ = 18240962. Its totient is φ = 18240960.

The previous prime is 18240919. The next prime is 18240967. The reversal of 18240961 is 16904281.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13830961 + 4410000 = 3719^2 + 2100^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18240961 is a prime.

It is not a weakly prime, because it can be changed into another prime (18240967) 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, 9120480 + 9120481.

It is an arithmetic number, because the mean of its divisors is an integer number (9120481).

Almost surely, 2^18240961 is an apocalyptic number.

It is an amenable number.

18240961 is a deficient number, since it is larger than the sum of its proper divisors (1).

18240961 is an equidigital number, since it uses as much as digits as its factorization.

18240961 is an odious number, because the sum of its binary digits is odd.

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

The square root of 18240961 is about 4270.9438067013. The cubic root of 18240961 is about 263.2383974754.

The spelling of 18240961 in words is "eighteen million, two hundred forty thousand, nine hundred sixty-one".