18773149 has 2 divisors, whose sum is σ = 18773150. Its totient is φ = 18773148.

The previous prime is 18773143. The next prime is 18773213. The reversal of 18773149 is 94137781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18062500 + 710649 = 4250^2 + 843^2 .

It is a cyclic number.

It is not a de Polignac number, because 18773149 - 2³ = 18773141 is a prime.

It is a super-2 number, since 2×18773149² = 704862246752402, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18773141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9386574 + 9386575.

It is an arithmetic number, because the mean of its divisors is an integer number (9386575).

Almost surely, 2^18773149 is an apocalyptic number.

It is an amenable number.

18773149 is a deficient number, since it is larger than the sum of its proper divisors (1).

18773149 is an equidigital number, since it uses as much as digits as its factorization.

18773149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 40.

The square root of 18773149 is about 4332.7992106720. The cubic root of 18773149 is about 265.7739283692.

The spelling of 18773149 in words is "eighteen million, seven hundred seventy-three thousand, one hundred forty-nine".