18394649293 has 2 divisors, whose sum is σ = 18394649294. Its totient is φ = 18394649292.

The previous prime is 18394649261. The next prime is 18394649297. The reversal of 18394649293 is 39294649381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18232290729 + 162358564 = 135027^2 + 12742^2 .

It is a cyclic number.

It is not a de Polignac number, because 18394649293 - 2⁵ = 18394649261 is a prime.

It is a super-2 number, since 2×18394649293² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18394649297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9197324646 + 9197324647.

It is an arithmetic number, because the mean of its divisors is an integer number (9197324647).

Almost surely, 2^18394649293 is an apocalyptic number.

It is an amenable number.

18394649293 is a deficient number, since it is larger than the sum of its proper divisors (1).

18394649293 is an equidigital number, since it uses as much as digits as its factorization.

18394649293 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10077696, while the sum is 58.

The spelling of 18394649293 in words is "eighteen billion, three hundred ninety-four million, six hundred forty-nine thousand, two hundred ninety-three".