399742 has 12 divisors (see below), whose sum is σ = 697680. Its totient is φ = 171276.

The previous prime is 399739. The next prime is 399757. The reversal of 399742 is 247993.

It is a d-powerful number, because it can be written as 3¹¹ + 9² + 7⁶ + 9⁴ + 4⁸ + 2¹⁵ .

It is a junction number, because it is equal to n+sod(n) for n = 399698 and 399707.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1942 + ... + 2137.

It is an arithmetic number, because the mean of its divisors is an integer number (58140).

2³⁹⁹⁷⁴² is an apocalyptic number.

399742 is a deficient number, since it is larger than the sum of its proper divisors (297938).

399742 is a wasteful number, since it uses less digits than its factorization.

399742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4095 (or 4088 counting only the distinct ones).

The product of its digits is 13608, while the sum is 34.

The square root of 399742 is about 632.2515322243. The cubic root of 399742 is about 73.6647852303.

The spelling of 399742 in words is "three hundred ninety-nine thousand, seven hundred forty-two".