6420724 has 12 divisors (see below), whose sum is σ = 11295844. Its totient is φ = 3193344.

The previous prime is 6420709. The next prime is 6420731. The reversal of 6420724 is 4270246.

It can be written as a sum of positive squares in 2 ways, for example, as 4410000 + 2010724 = 2100^2 + 1418^2 .

It is a congruent number.

It is an unprimeable number.

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, 3387 + ... + 4930.

Almost surely, 2^6420724 is an apocalyptic number.

It is an amenable number.

6420724 is a deficient number, since it is larger than the sum of its proper divisors (4875120).

6420724 is a wasteful number, since it uses less digits than its factorization.

6420724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8514 (or 8512 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 6420724 is about 2533.9147578401. The cubic root of 6420724 is about 185.8637380233.

The spelling of 6420724 in words is "six million, four hundred twenty thousand, seven hundred twenty-four".