18959000521 has 2 divisors, whose sum is σ = 18959000522. Its totient is φ = 18959000520.

The previous prime is 18959000471. The next prime is 18959000537. The reversal of 18959000521 is 12500095981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16424985600 + 2534014921 = 128160^2 + 50339^2 .

It is an emirp because it is prime and its reverse (12500095981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18959000521 - 2⁷ = 18959000393 is a prime.

It is not a weakly prime, because it can be changed into another prime (18959000591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9479500260 + 9479500261.

It is an arithmetic number, because the mean of its divisors is an integer number (9479500261).

Almost surely, 2^18959000521 is an apocalyptic number.

It is an amenable number.

18959000521 is a deficient number, since it is larger than the sum of its proper divisors (1).

18959000521 is an equidigital number, since it uses as much as digits as its factorization.

18959000521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32400, while the sum is 40.

The spelling of 18959000521 in words is "eighteen billion, nine hundred fifty-nine million, five hundred twenty-one", and thus it is an aban number.