16390404025 has 6 divisors (see below), whose sum is σ = 20324101022. Its totient is φ = 13112323200.

The previous prime is 16390404007. The next prime is 16390404029. The reversal of 16390404025 is 52040409361.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 4143883129 + 12246520896 = 64373^2 + 110664^2 .

It is not a de Polignac number, because 16390404025 - 2⁵ = 16390403993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16390404029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 327808056 + ... + 327808105.

Almost surely, 2^16390404025 is an apocalyptic number.

It is an amenable number.

16390404025 is a deficient number, since it is larger than the sum of its proper divisors (3933696997).

16390404025 is an equidigital number, since it uses as much as digits as its factorization.

16390404025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 655616171 (or 655616166 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 34.

The spelling of 16390404025 in words is "sixteen billion, three hundred ninety million, four hundred four thousand, twenty-five".