18026307925721 has 2 divisors, whose sum is σ = 18026307925722. Its totient is φ = 18026307925720.

The previous prime is 18026307925559. The next prime is 18026307925723. The reversal of 18026307925721 is 12752970362081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10913845639321 + 7112462286400 = 3303611^2 + 2666920^2 .

It is an emirp because it is prime and its reverse (12752970362081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18026307925721 - 2³⁰ = 18025234183897 is a prime.

Together with 18026307925723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18026307925723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9013153962860 + 9013153962861.

It is an arithmetic number, because the mean of its divisors is an integer number (9013153962861).

Almost surely, 2^{18026307925721} is an apocalyptic number.

It is an amenable number.

18026307925721 is a deficient number, since it is larger than the sum of its proper divisors (1).

18026307925721 is an equidigital number, since it uses as much as digits as its factorization.

18026307925721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2540160, while the sum is 53.

The spelling of 18026307925721 in words is "eighteen trillion, twenty-six billion, three hundred seven million, nine hundred twenty-five thousand, seven hundred twenty-one".