1640825 has 6 divisors (see below), whose sum is σ = 2034654. Its totient is φ = 1312640.

The previous prime is 1640819. The next prime is 1640833. The reversal of 1640825 is 5280461.

It can be written as a sum of positive squares in 3 ways, for example, as 219961 + 1420864 = 469^2 + 1192^2 .

It is not a de Polignac number, because 1640825 - 2⁴ = 1640809 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1640794 and 1640803.

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, 32792 + ... + 32841.

It is an arithmetic number, because the mean of its divisors is an integer number (339109).

2^1640825 is an apocalyptic number.

It is an amenable number.

1640825 is a deficient number, since it is larger than the sum of its proper divisors (393829).

1640825 is an equidigital number, since it uses as much as digits as its factorization.

1640825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65643 (or 65638 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 1640825 is about 1280.9469153716. The cubic root of 1640825 is about 117.9471418912.

The spelling of 1640825 in words is "one million, six hundred forty thousand, eight hundred twenty-five".