18640723 has 2 divisors, whose sum is σ = 18640724. Its totient is φ = 18640722.

The previous prime is 18640693. The next prime is 18640751. The reversal of 18640723 is 32704681.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18640723 - 2¹³ = 18632531 is a prime.

It is not a weakly prime, because it can be changed into another prime (18640753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9320361 + 9320362.

It is an arithmetic number, because the mean of its divisors is an integer number (9320362).

Almost surely, 2^18640723 is an apocalyptic number.

18640723 is a deficient number, since it is larger than the sum of its proper divisors (1).

18640723 is an equidigital number, since it uses as much as digits as its factorization.

18640723 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 18640723 is about 4317.4903589933. The cubic root of 18640723 is about 265.1475291029.

The spelling of 18640723 in words is "eighteen million, six hundred forty thousand, seven hundred twenty-three".