18709573 has 2 divisors, whose sum is σ = 18709574. Its totient is φ = 18709572.

The previous prime is 18709519. The next prime is 18709589. The reversal of 18709573 is 37590781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9847044 + 8862529 = 3138^2 + 2977^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18709573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18706573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9354786 + 9354787.

It is an arithmetic number, because the mean of its divisors is an integer number (9354787).

Almost surely, 2^18709573 is an apocalyptic number.

It is an amenable number.

18709573 is a deficient number, since it is larger than the sum of its proper divisors (1).

18709573 is an equidigital number, since it uses as much as digits as its factorization.

18709573 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52920, while the sum is 40.

The square root of 18709573 is about 4325.4563921048. The cubic root of 18709573 is about 265.4735711377.

The spelling of 18709573 in words is "eighteen million, seven hundred nine thousand, five hundred seventy-three".