6400247 has 4 divisors (see below), whose sum is σ = 7314576. Its totient is φ = 5485920.

The previous prime is 6400241. The next prime is 6400253. The reversal of 6400247 is 7420046.

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

It is an interprime number because it is at equal distance from previous prime (6400241) and next prime (6400253).

It is a cyclic number.

It is not a de Polignac number, because 6400247 - 2⁴ = 6400231 is a prime.

It is a super-2 number, since 2×6400247² = 81926323322018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6400241) 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 in 3 ways as a sum of consecutive naturals, for example, 457154 + ... + 457167.

It is an arithmetic number, because the mean of its divisors is an integer number (1828644).

Almost surely, 2^6400247 is an apocalyptic number.

6400247 is a deficient number, since it is larger than the sum of its proper divisors (914329).

6400247 is an equidigital number, since it uses as much as digits as its factorization.

6400247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 914328.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 6400247 is about 2529.8709453251. The cubic root of 6400247 is about 185.6659417980.

The spelling of 6400247 in words is "six million, four hundred thousand, two hundred forty-seven".