18918358913 has 2 divisors, whose sum is σ = 18918358914. Its totient is φ = 18918358912.

The previous prime is 18918358903. The next prime is 18918359041. The reversal of 18918358913 is 31985381981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15304906369 + 3613452544 = 123713^2 + 60112^2 .

It is a cyclic number.

It is not a de Polignac number, because 18918358913 - 2¹⁰ = 18918357889 is a prime.

It is a super-2 number, since 2×18918358913² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18918358903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9459179456 + 9459179457.

It is an arithmetic number, because the mean of its divisors is an integer number (9459179457).

Almost surely, 2^18918358913 is an apocalyptic number.

It is an amenable number.

18918358913 is a deficient number, since it is larger than the sum of its proper divisors (1).

18918358913 is an equidigital number, since it uses as much as digits as its factorization.

18918358913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1866240, while the sum is 56.

The spelling of 18918358913 in words is "eighteen billion, nine hundred eighteen million, three hundred fifty-eight thousand, nine hundred thirteen".