18945541 has 2 divisors, whose sum is σ = 18945542. Its totient is φ = 18945540.

The previous prime is 18945529. The next prime is 18945547. The reversal of 18945541 is 14554981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15444900 + 3500641 = 3930^2 + 1871^2 .

It is a cyclic number.

It is not a de Polignac number, because 18945541 - 2⁹ = 18945029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18945541.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18945547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9472770 + 9472771.

It is an arithmetic number, because the mean of its divisors is an integer number (9472771).

Almost surely, 2^18945541 is an apocalyptic number.

It is an amenable number.

18945541 is a deficient number, since it is larger than the sum of its proper divisors (1).

18945541 is an equidigital number, since it uses as much as digits as its factorization.

18945541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 28800, while the sum is 37.

The square root of 18945541 is about 4352.6475850912. The cubic root of 18945541 is about 266.5849761928.

The spelling of 18945541 in words is "eighteen million, nine hundred forty-five thousand, five hundred forty-one".