399655 has 8 divisors (see below), whose sum is σ = 487152. Its totient is φ = 314688.

The previous prime is 399647. The next prime is 399667. The reversal of 399655 is 556993.

399655 = T₇₄ + T₇₅ + ... + T₁₄₀.

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 399655 - 2³ = 399647 is a prime.

It is a Duffinian number.

399655 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 262 + ... + 931.

It is an arithmetic number, because the mean of its divisors is an integer number (60894).

2³⁹⁹⁶⁵⁵ is an apocalyptic number.

399655 is a deficient number, since it is larger than the sum of its proper divisors (87497).

399655 is a wasteful number, since it uses less digits than its factorization.

399655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1265.

The product of its digits is 36450, while the sum is 37.

The square root of 399655 is about 632.1827267492. The cubic root of 399655 is about 73.6594406986.

The spelling of 399655 in words is "three hundred ninety-nine thousand, six hundred fifty-five".