18521019523 has 2 divisors, whose sum is σ = 18521019524. Its totient is φ = 18521019522.

The previous prime is 18521019511. The next prime is 18521019541. The reversal of 18521019523 is 32591012581.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18521019523 - 2¹³ = 18521011331 is a prime.

It is not a weakly prime, because it can be changed into another prime (18521016523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9260509761 + 9260509762.

It is an arithmetic number, because the mean of its divisors is an integer number (9260509762).

Almost surely, 2^18521019523 is an apocalyptic number.

18521019523 is a deficient number, since it is larger than the sum of its proper divisors (1).

18521019523 is an equidigital number, since it uses as much as digits as its factorization.

18521019523 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 37.

The spelling of 18521019523 in words is "eighteen billion, five hundred twenty-one million, nineteen thousand, five hundred twenty-three".