18957149 has 2 divisors, whose sum is σ = 18957150. Its totient is φ = 18957148.

The previous prime is 18957139. The next prime is 18957161. The reversal of 18957149 is 94175981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16728100 + 2229049 = 4090^2 + 1493^2 .

It is an emirp because it is prime and its reverse (94175981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18957149 - 2⁸ = 18956893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18957119) 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, 9478574 + 9478575.

It is an arithmetic number, because the mean of its divisors is an integer number (9478575).

Almost surely, 2^18957149 is an apocalyptic number.

It is an amenable number.

18957149 is a deficient number, since it is larger than the sum of its proper divisors (1).

18957149 is an equidigital number, since it uses as much as digits as its factorization.

18957149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 44.

The square root of 18957149 is about 4353.9808221902. The cubic root of 18957149 is about 266.6394109296.

The spelling of 18957149 in words is "eighteen million, nine hundred fifty-seven thousand, one hundred forty-nine".