399897 has 10 divisors (see below), whose sum is σ = 597498. Its totient is φ = 266544.

The previous prime is 399887. The next prime is 399899. The reversal of 399897 is 798993.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 331776 + 68121 = 576^2 + 261^2 .

It is not a de Polignac number, because 399897 - 2⁷ = 399769 is a prime.

It is a super-2 number, since 2×399897² = 319835221218, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (399899) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 2388 + ... + 2549.

2³⁹⁹⁸⁹⁷ is an apocalyptic number.

It is an amenable number.

399897 is a deficient number, since it is larger than the sum of its proper divisors (197601).

399897 is an equidigital number, since it uses as much as digits as its factorization.

399897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4949 (or 4940 counting only the distinct ones).

The product of its digits is 122472, while the sum is 45.

The square root of 399897 is about 632.3740981413. The cubic root of 399897 is about 73.6743051758.

It can be divided in two parts, 3998 and 97, that added together give a triangular number (4095 = T₉₀).

The spelling of 399897 in words is "three hundred ninety-nine thousand, eight hundred ninety-seven".