18949717 has 2 divisors, whose sum is σ = 18949718. Its totient is φ = 18949716.

The previous prime is 18949681. The next prime is 18949727. The reversal of 18949717 is 71794981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18887716 + 62001 = 4346^2 + 249^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18949717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18949727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9474858 + 9474859.

It is an arithmetic number, because the mean of its divisors is an integer number (9474859).

Almost surely, 2^18949717 is an apocalyptic number.

It is an amenable number.

18949717 is a deficient number, since it is larger than the sum of its proper divisors (1).

18949717 is an equidigital number, since it uses as much as digits as its factorization.

18949717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 46.

The square root of 18949717 is about 4353.1272666900. The cubic root of 18949717 is about 266.6045617526.

It can be divided in two parts, 1894 and 9717, that added together give a palindrome (11611).

The spelling of 18949717 in words is "eighteen million, nine hundred forty-nine thousand, seven hundred seventeen".