1645625 has 10 divisors (see below), whose sum is σ = 2057154. Its totient is φ = 1316000.

The previous prime is 1645613. The next prime is 1645643. The reversal of 1645625 is 5265461.

It can be written as a sum of positive squares in 5 ways, for example, as 946729 + 698896 = 973^2 + 836^2 .

It is not a de Polignac number, because 1645625 - 2⁶ = 1645561 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 692 + ... + 1941.

2^1645625 is an apocalyptic number.

It is an amenable number.

1645625 is a deficient number, since it is larger than the sum of its proper divisors (411529).

1645625 is an frugal number, since it uses more digits than its factorization.

1645625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2653 (or 2638 counting only the distinct ones).

The product of its digits is 7200, while the sum is 29.

The square root of 1645625 is about 1282.8191610667. The cubic root of 1645625 is about 118.0620424476.

The spelling of 1645625 in words is "one million, six hundred forty-five thousand, six hundred twenty-five".