19780825 has 6 divisors (see below), whose sum is σ = 24528254. Its totient is φ = 15824640.

The previous prime is 19780781. The next prime is 19780837. The reversal of 19780825 is 52808791.

It can be written as a sum of positive squares in 3 ways, for example, as 1565001 + 18215824 = 1251^2 + 4268^2 .

It is not a de Polignac number, because 19780825 - 2¹¹ = 19778777 is a prime.

It is a Duffinian number.

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, 395592 + ... + 395641.

Almost surely, 2^19780825 is an apocalyptic number.

It is an amenable number.

19780825 is a deficient number, since it is larger than the sum of its proper divisors (4747429).

19780825 is an equidigital number, since it uses as much as digits as its factorization.

19780825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791243 (or 791238 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 19780825 is about 4447.5639399563. The cubic root of 19780825 is about 270.4465632454.

The spelling of 19780825 in words is "nineteen million, seven hundred eighty thousand, eight hundred twenty-five".