6421825 has 6 divisors (see below), whose sum is σ = 7963094. Its totient is φ = 5137440.

The previous prime is 6421817. The next prime is 6421841. The reversal of 6421825 is 5281246.

It can be written as a sum of positive squares in 3 ways, for example, as 156816 + 6265009 = 396^2 + 2503^2 .

It is not a de Polignac number, because 6421825 - 2³ = 6421817 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6421793 and 6421802.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 128412 + ... + 128461.

Almost surely, 2^6421825 is an apocalyptic number.

It is an amenable number.

6421825 is a deficient number, since it is larger than the sum of its proper divisors (1541269).

6421825 is a wasteful number, since it uses less digits than its factorization.

6421825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256883 (or 256878 counting only the distinct ones).

The product of its digits is 3840, while the sum is 28.

The square root of 6421825 is about 2534.1320012975. The cubic root of 6421825 is about 185.8743611389.

The spelling of 6421825 in words is "six million, four hundred twenty-one thousand, eight hundred twenty-five".