389688391661 has 2 divisors, whose sum is σ = 389688391662. Its totient is φ = 389688391660.

The previous prime is 389688391637. The next prime is 389688391681. The reversal of 389688391661 is 166193886983.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 354107114761 + 35581276900 = 595069^2 + 188630^2 .

It is a cyclic number.

It is not a de Polignac number, because 389688391661 - 2¹⁴ = 389688375277 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 389688391591 and 389688391600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (389688391681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194844195830 + 194844195831.

It is an arithmetic number, because the mean of its divisors is an integer number (194844195831).

Almost surely, 2^389688391661 is an apocalyptic number.

It is an amenable number.

389688391661 is a deficient number, since it is larger than the sum of its proper divisors (1).

389688391661 is an equidigital number, since it uses as much as digits as its factorization.

389688391661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80621568, while the sum is 68.

The spelling of 389688391661 in words is "three hundred eighty-nine billion, six hundred eighty-eight million, three hundred ninety-one thousand, six hundred sixty-one".