399455 has 16 divisors (see below), whose sum is σ = 558144. Its totient is φ = 268800.

The previous prime is 399439. The next prime is 399473. The reversal of 399455 is 554993.

399455 = T₂₁ + T₂₂ + ... + T₁₃₃.

It is not a de Polignac number, because 399455 - 2⁴ = 399439 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a d-powerful number, because it can be written as 3 + 9 + 4⁹ + 9⁵ + 5³ + 5⁷ .

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3479 + ... + 3591.

It is an arithmetic number, because the mean of its divisors is an integer number (34884).

2³⁹⁹⁴⁵⁵ is an apocalyptic number.

399455 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

399455 is a deficient number, since it is larger than the sum of its proper divisors (158689).

399455 is a wasteful number, since it uses less digits than its factorization.

399455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226.

The product of its digits is 24300, while the sum is 35.

The square root of 399455 is about 632.0245248406. The cubic root of 399455 is about 73.6471514773.

The spelling of 399455 in words is "three hundred ninety-nine thousand, four hundred fifty-five".