618563993 has 2 divisors, whose sum is σ = 618563994. Its totient is φ = 618563992.

The previous prime is 618563983. The next prime is 618564017. The reversal of 618563993 is 399365816.

618563993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 479960464 + 138603529 = 21908^2 + 11773^2 .

It is a cyclic number.

It is not a de Polignac number, because 618563993 - 2¹² = 618559897 is a prime.

It is a super-2 number, since 2×618563993² = 765242826872208098, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (618563903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309281996 + 309281997.

It is an arithmetic number, because the mean of its divisors is an integer number (309281997).

Almost surely, 2^618563993 is an apocalyptic number.

It is an amenable number.

618563993 is a deficient number, since it is larger than the sum of its proper divisors (1).

618563993 is an equidigital number, since it uses as much as digits as its factorization.

618563993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1049760, while the sum is 50.

The square root of 618563993 is about 24870.9467652520. The cubic root of 618563993 is about 852.0430636649.

The spelling of 618563993 in words is "six hundred eighteen million, five hundred sixty-three thousand, nine hundred ninety-three".