389198509681 has 2 divisors, whose sum is σ = 389198509682. Its totient is φ = 389198509680.

The previous prime is 389198509649. The next prime is 389198509697. The reversal of 389198509681 is 186905891983.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 263800368225 + 125398141456 = 513615^2 + 354116^2 .

It is an emirp because it is prime and its reverse (186905891983) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 389198509681 - 2⁵ = 389198509649 is a prime.

It is a super-2 number, since 2×389198509681² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (389198509481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194599254840 + 194599254841.

It is an arithmetic number, because the mean of its divisors is an integer number (194599254841).

Almost surely, 2^389198509681 is an apocalyptic number.

It is an amenable number.

389198509681 is a deficient number, since it is larger than the sum of its proper divisors (1).

389198509681 is an equidigital number, since it uses as much as digits as its factorization.

389198509681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33592320, while the sum is 67.

The spelling of 389198509681 in words is "three hundred eighty-nine billion, one hundred ninety-eight million, five hundred nine thousand, six hundred eighty-one".