18645673 has 2 divisors, whose sum is σ = 18645674. Its totient is φ = 18645672.

The previous prime is 18645643. The next prime is 18645689. The reversal of 18645673 is 37654681.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17040384 + 1605289 = 4128^2 + 1267^2 .

It is an emirp because it is prime and its reverse (37654681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18645673 - 2⁹ = 18645161 is a prime.

It is a super-2 number, since 2×18645673² = 695322243245858, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18645643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9322836 + 9322837.

It is an arithmetic number, because the mean of its divisors is an integer number (9322837).

Almost surely, 2^18645673 is an apocalyptic number.

It is an amenable number.

18645673 is a deficient number, since it is larger than the sum of its proper divisors (1).

18645673 is an equidigital number, since it uses as much as digits as its factorization.

18645673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 40.

The square root of 18645673 is about 4318.0635706298. The cubic root of 18645673 is about 265.1709967926.

The spelling of 18645673 in words is "eighteen million, six hundred forty-five thousand, six hundred seventy-three".