399991697 has 8 divisors (see below), whose sum is σ = 458409600. Its totient is φ = 341892864.

The previous prime is 399991663. The next prime is 399991727. The reversal of 399991697 is 796199993.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 399991697 - 2¹⁰ = 399990673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399991607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77072 + ... + 82097.

It is an arithmetic number, because the mean of its divisors is an integer number (57301200).

Almost surely, 2^399991697 is an apocalyptic number.

It is an amenable number.

399991697 is a deficient number, since it is larger than the sum of its proper divisors (58417903).

399991697 is a wasteful number, since it uses less digits than its factorization.

399991697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159535.

The product of its digits is 7440174, while the sum is 62.

The square root of 399991697 is about 19999.7924239228. The cubic root of 399991697 is about 736.8012016072.

The spelling of 399991697 in words is "three hundred ninety-nine million, nine hundred ninety-one thousand, six hundred ninety-seven".