399693671 has 16 divisors (see below), whose sum is σ = 460790400. Its totient is φ = 343592928.

The previous prime is 399693653. The next prime is 399693673. The reversal of 399693671 is 176396993.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 399693671 - 2⁶ = 399693607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399693673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 860 + ... + 28286.

It is an arithmetic number, because the mean of its divisors is an integer number (28799400).

Almost surely, 2^399693671 is an apocalyptic number.

399693671 is a deficient number, since it is larger than the sum of its proper divisors (61096729).

399693671 is a wasteful number, since it uses less digits than its factorization.

399693671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27518.

The product of its digits is 1653372, while the sum is 53.

The square root of 399693671 is about 19992.3403082280. The cubic root of 399693671 is about 736.6181640796.

The spelling of 399693671 in words is "three hundred ninety-nine million, six hundred ninety-three thousand, six hundred seventy-one".