18393479729 has 2 divisors, whose sum is σ = 18393479730. Its totient is φ = 18393479728.

The previous prime is 18393479717. The next prime is 18393479747. The reversal of 18393479729 is 92797439381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10954762225 + 7438717504 = 104665^2 + 86248^2 .

It is an emirp because it is prime and its reverse (92797439381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18393479729 - 2²⁰ = 18392431153 is a prime.

It is a super-2 number, since 2×18393479729² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18393479759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9196739864 + 9196739865.

It is an arithmetic number, because the mean of its divisors is an integer number (9196739865).

Almost surely, 2^18393479729 is an apocalyptic number.

It is an amenable number.

18393479729 is a deficient number, since it is larger than the sum of its proper divisors (1).

18393479729 is an equidigital number, since it uses as much as digits as its factorization.

18393479729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20575296, while the sum is 62.

The spelling of 18393479729 in words is "eighteen billion, three hundred ninety-three million, four hundred seventy-nine thousand, seven hundred twenty-nine".