18251331793 has 2 divisors, whose sum is σ = 18251331794. Its totient is φ = 18251331792.

The previous prime is 18251331757. The next prime is 18251331863. The reversal of 18251331793 is 39713315281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14225809984 + 4025521809 = 119272^2 + 63447^2 .

It is an emirp because it is prime and its reverse (39713315281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18251331793 - 2⁹ = 18251331281 is a prime.

It is a super-2 number, since 2×18251331793² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18251331893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9125665896 + 9125665897.

It is an arithmetic number, because the mean of its divisors is an integer number (9125665897).

Almost surely, 2^18251331793 is an apocalyptic number.

It is an amenable number.

18251331793 is a deficient number, since it is larger than the sum of its proper divisors (1).

18251331793 is an equidigital number, since it uses as much as digits as its factorization.

18251331793 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 43.

The spelling of 18251331793 in words is "eighteen billion, two hundred fifty-one million, three hundred thirty-one thousand, seven hundred ninety-three".