6447021 has 16 divisors (see below), whose sum is σ = 9859584. Its totient is φ = 3670704.

The previous prime is 6447017. The next prime is 6447031. The reversal of 6447021 is 1207446.

It is not a de Polignac number, because 6447021 - 2² = 6447017 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6446982 and 6447000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6447031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10690 + ... + 11276.

It is an arithmetic number, because the mean of its divisors is an integer number (616224).

Almost surely, 2^6447021 is an apocalyptic number.

It is an amenable number.

6447021 is a deficient number, since it is larger than the sum of its proper divisors (3412563).

6447021 is a wasteful number, since it uses less digits than its factorization.

6447021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1120.

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 6447021 is about 2539.0984620530. The cubic root of 6447021 is about 186.1171362983.

The spelling of 6447021 in words is "six million, four hundred forty-seven thousand, twenty-one".