394033369781 has 2 divisors, whose sum is σ = 394033369782. Its totient is φ = 394033369780.

The previous prime is 394033369729. The next prime is 394033369801. The reversal of 394033369781 is 187963330493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 291239391556 + 102793978225 = 539666^2 + 320615^2 .

It is a cyclic number.

It is not a de Polignac number, because 394033369781 - 2¹⁴ = 394033353397 is a prime.

It is a super-2 number, since 2×394033369781² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (394033369711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197016684890 + 197016684891.

It is an arithmetic number, because the mean of its divisors is an integer number (197016684891).

Almost surely, 2^394033369781 is an apocalyptic number.

It is an amenable number.

394033369781 is a deficient number, since it is larger than the sum of its proper divisors (1).

394033369781 is an equidigital number, since it uses as much as digits as its factorization.

394033369781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8817984, while the sum is 56.

The spelling of 394033369781 in words is "three hundred ninety-four billion, thirty-three million, three hundred sixty-nine thousand, seven hundred eighty-one".