18477749 has 2 divisors, whose sum is σ = 18477750. Its totient is φ = 18477748.

The previous prime is 18477743. The next prime is 18477751. The reversal of 18477749 is 94777481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14577124 + 3900625 = 3818^2 + 1975^2 .

It is a cyclic number.

It is not a de Polignac number, because 18477749 - 2⁴ = 18477733 is a prime.

Together with 18477751, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18477743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9238874 + 9238875.

It is an arithmetic number, because the mean of its divisors is an integer number (9238875).

Almost surely, 2^18477749 is an apocalyptic number.

It is an amenable number.

18477749 is a deficient number, since it is larger than the sum of its proper divisors (1).

18477749 is an equidigital number, since it uses as much as digits as its factorization.

18477749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 395136, while the sum is 47.

The square root of 18477749 is about 4298.5752290730. The cubic root of 18477749 is about 264.3725466112.

The spelling of 18477749 in words is "eighteen million, four hundred seventy-seven thousand, seven hundred forty-nine".