399547 has 4 divisors (see below), whose sum is σ = 408096. Its totient is φ = 391000.

The previous prime is 399541. The next prime is 399557. The reversal of 399547 is 745993.

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-399547 is a prime.

It is a Duffinian number.

399547 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (399541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4204 + ... + 4297.

It is an arithmetic number, because the mean of its divisors is an integer number (102024).

2³⁹⁹⁵⁴⁷ is an apocalyptic number.

399547 is a deficient number, since it is larger than the sum of its proper divisors (8549).

399547 is an equidigital number, since it uses as much as digits as its factorization.

399547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8548.

The product of its digits is 34020, while the sum is 37.

The square root of 399547 is about 632.0973026362. The cubic root of 399547 is about 73.6528050284.

It can be divided in two parts, 399 and 547, that added together give a triangular number (946 = T₄₃).

The spelling of 399547 in words is "three hundred ninety-nine thousand, five hundred forty-seven".