18759649 has 2 divisors, whose sum is σ = 18759650. Its totient is φ = 18759648.

The previous prime is 18759617. The next prime is 18759661. The reversal of 18759649 is 94695781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14630625 + 4129024 = 3825^2 + 2032^2 .

It is an emirp because it is prime and its reverse (94695781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18759649 - 2⁵ = 18759617 is a prime.

It is not a weakly prime, because it can be changed into another prime (18759679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9379824 + 9379825.

It is an arithmetic number, because the mean of its divisors is an integer number (9379825).

Almost surely, 2^18759649 is an apocalyptic number.

It is an amenable number.

18759649 is a deficient number, since it is larger than the sum of its proper divisors (1).

18759649 is an equidigital number, since it uses as much as digits as its factorization.

18759649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 49.

The square root of 18759649 is about 4331.2410461668. The cubic root of 18759649 is about 265.7102060030.

The spelling of 18759649 in words is "eighteen million, seven hundred fifty-nine thousand, six hundred forty-nine".