397906 has 4 divisors (see below), whose sum is σ = 596862. Its totient is φ = 198952.

The previous prime is 397897. The next prime is 397907. The reversal of 397906 is 609793.

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

It can be written as a sum of positive squares in only one way, i.e., 245025 + 152881 = 495^2 + 391^2 .

It is not an unprimeable number, because it can be changed into a prime (397907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99475 + ... + 99478.

2³⁹⁷⁹⁰⁶ is an apocalyptic number.

397906 is a deficient number, since it is larger than the sum of its proper divisors (198956).

397906 is a wasteful number, since it uses less digits than its factorization.

397906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198955.

The product of its (nonzero) digits is 10206, while the sum is 34.

The square root of 397906 is about 630.7979074157. The cubic root of 397906 is about 73.5518322593.

The spelling of 397906 in words is "three hundred ninety-seven thousand, nine hundred six".