6450021 has 12 divisors (see below), whose sum is σ = 9864972. Its totient is φ = 4046976.

The previous prime is 6450019. The next prime is 6450029. The reversal of 6450021 is 1200546.

It is a happy number.

6450021 is a `hidden beast` number, since 645 + 0 + 0 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3101121 + 3348900 = 1761^2 + 1830^2 .

It is not a de Polignac number, because 6450021 - 2¹ = 6450019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6449976 and 6450003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6450029) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20926 + ... + 21231.

It is an arithmetic number, because the mean of its divisors is an integer number (822081).

Almost surely, 2^6450021 is an apocalyptic number.

It is an amenable number.

6450021 is a deficient number, since it is larger than the sum of its proper divisors (3414951).

6450021 is a wasteful number, since it uses less digits than its factorization.

6450021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42180 (or 42177 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 6450021 is about 2539.6891542077. The cubic root of 6450021 is about 186.1460005249.

Adding to 6450021 its reverse (1200546), we get a palindrome (7650567).

The spelling of 6450021 in words is "six million, four hundred fifty thousand, twenty-one".