6397906 has 4 divisors (see below), whose sum is σ = 9596862. Its totient is φ = 3198952.

The previous prime is 6397903. The next prime is 6397921. The reversal of 6397906 is 6097936.

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., 6027025 + 370881 = 2455^2 + 609^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (6397903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1599475 + ... + 1599478.

Almost surely, 2^6397906 is an apocalyptic number.

6397906 is a deficient number, since it is larger than the sum of its proper divisors (3198956).

6397906 is a wasteful number, since it uses less digits than its factorization.

6397906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3198955.

The product of its (nonzero) digits is 61236, while the sum is 40.

The square root of 6397906 is about 2529.4082311877. The cubic root of 6397906 is about 185.6433022044.

It can be divided in two parts, 63 and 97906, that added together give a square (97969 = 313²).

The spelling of 6397906 in words is "six million, three hundred ninety-seven thousand, nine hundred six".