18904475729 has 2 divisors, whose sum is σ = 18904475730. Its totient is φ = 18904475728.

The previous prime is 18904475699. The next prime is 18904475747. The reversal of 18904475729 is 92757440981.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18872440129 + 32035600 = 137377^2 + 5660^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18904475729 is a prime.

It is not a weakly prime, because it can be changed into another prime (18904475789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9452237864 + 9452237865.

It is an arithmetic number, because the mean of its divisors is an integer number (9452237865).

Almost surely, 2^18904475729 is an apocalyptic number.

It is an amenable number.

18904475729 is a deficient number, since it is larger than the sum of its proper divisors (1).

18904475729 is an equidigital number, since it uses as much as digits as its factorization.

18904475729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5080320, while the sum is 56.

The spelling of 18904475729 in words is "eighteen billion, nine hundred four million, four hundred seventy-five thousand, seven hundred twenty-nine".