20404425 has 12 divisors (see below), whose sum is σ = 33735440. Its totient is φ = 10882320.

The previous prime is 20404421. The next prime is 20404441. The reversal of 20404425 is 52440402.

It is not a de Polignac number, because 20404425 - 2² = 20404421 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20404421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 135955 + ... + 136104.

Almost surely, 2^20404425 is an apocalyptic number.

20404425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20404425 is a deficient number, since it is larger than the sum of its proper divisors (13331015).

20404425 is a wasteful number, since it uses less digits than its factorization.

20404425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272072 (or 272067 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 21.

The square root of 20404425 is about 4517.1257454271. The cubic root of 20404425 is about 273.2591964643.

Adding to 20404425 its reverse (52440402), we get a palindrome (72844827).

The spelling of 20404425 in words is "twenty million, four hundred four thousand, four hundred twenty-five".