399611 has 4 divisors (see below), whose sum is σ = 406224. Its totient is φ = 393000.

The previous prime is 399601. The next prime is 399613. The reversal of 399611 is 116993.

399611 = 49² + 50² + ... + 109².

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399613) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3215 + ... + 3336.

It is an arithmetic number, because the mean of its divisors is an integer number (101556).

2³⁹⁹⁶¹¹ is an apocalyptic number.

399611 is a deficient number, since it is larger than the sum of its proper divisors (6613).

399611 is an equidigital number, since it uses as much as digits as its factorization.

399611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6612.

The product of its digits is 1458, while the sum is 29.

The square root of 399611 is about 632.1479257262. The cubic root of 399611 is about 73.6567374217.

It can be divided in two parts, 3996 and 11, that multiplied together give a triangular number (43956 = T₂₉₆).

The spelling of 399611 in words is "three hundred ninety-nine thousand, six hundred eleven".