393389081 has 2 divisors, whose sum is σ = 393389082. Its totient is φ = 393389080.

The previous prime is 393389063. The next prime is 393389123. The reversal of 393389081 is 180983393.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 387459856 + 5929225 = 19684^2 + 2435^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-393389081 is a prime.

It is a super-2 number, since 2×393389081² = 309509938100049122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (393389011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 196694540 + 196694541.

It is an arithmetic number, because the mean of its divisors is an integer number (196694541).

Almost surely, 2^393389081 is an apocalyptic number.

It is an amenable number.

393389081 is a deficient number, since it is larger than the sum of its proper divisors (1).

393389081 is an equidigital number, since it uses as much as digits as its factorization.

393389081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 393389081 is about 19834.0384440487. The cubic root of 393389081 is about 732.7245909411.

The spelling of 393389081 in words is "three hundred ninety-three million, three hundred eighty-nine thousand, eighty-one".