394781385769 has 4 divisors (see below), whose sum is σ = 418003820244. Its totient is φ = 371558951296.

The previous prime is 394781385743. The next prime is 394781385781. The reversal of 394781385769 is 967583187493.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 324913680144 + 69867705625 = 570012^2 + 264325^2 .

It is a cyclic number.

It is not a de Polignac number, because 394781385769 - 2¹¹ = 394781383721 is a prime.

It is a super-2 number, since 2×394781385769² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 394781385698 and 394781385707.

It is not an unprimeable number, because it can be changed into a prime (394781385709) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11611217212 + ... + 11611217245.

It is an arithmetic number, because the mean of its divisors is an integer number (104500955061).

Almost surely, 2^394781385769 is an apocalyptic number.

It is an amenable number.

394781385769 is a deficient number, since it is larger than the sum of its proper divisors (23222434475).

394781385769 is a wasteful number, since it uses less digits than its factorization.

394781385769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23222434474.

The product of its digits is 274337280, while the sum is 70.

The spelling of 394781385769 in words is "three hundred ninety-four billion, seven hundred eighty-one million, three hundred eighty-five thousand, seven hundred sixty-nine".