399785017 has 4 divisors (see below), whose sum is σ = 401993956. Its totient is φ = 397576080.

The previous prime is 399784991. The next prime is 399785041. The reversal of 399785017 is 710587993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 710587993 = 859 ⋅827227.

It can be written as a sum of positive squares in 2 ways, for example, as 181602576 + 218182441 = 13476^2 + 14771^2 .

It is a cyclic number.

It is not a de Polignac number, because 399785017 - 2¹¹ = 399782969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399785417) 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, 1104198 + ... + 1104559.

It is an arithmetic number, because the mean of its divisors is an integer number (100498489).

Almost surely, 2^399785017 is an apocalyptic number.

It is an amenable number.

399785017 is a deficient number, since it is larger than the sum of its proper divisors (2208939).

399785017 is a wasteful number, since it uses less digits than its factorization.

399785017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2208938.

The product of its (nonzero) digits is 476280, while the sum is 49.

The square root of 399785017 is about 19994.6247026545. The cubic root of 399785017 is about 736.6742753821.

The spelling of 399785017 in words is "three hundred ninety-nine million, seven hundred eighty-five thousand, seventeen".