20252405 has 4 divisors (see below), whose sum is σ = 24302892. Its totient is φ = 16201920.

The previous prime is 20252381. The next prime is 20252447. The reversal of 20252405 is 50425202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15194404 + 5058001 = 3898^2 + 2249^2 .

It is not a de Polignac number, because 20252405 - 2⁶ = 20252341 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2025236 + ... + 2025245.

It is an arithmetic number, because the mean of its divisors is an integer number (6075723).

Almost surely, 2^20252405 is an apocalyptic number.

It is an amenable number.

20252405 is a deficient number, since it is larger than the sum of its proper divisors (4050487).

20252405 is an equidigital number, since it uses as much as digits as its factorization.

20252405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4050486.

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 20252405 is about 4500.2672142885. The cubic root of 20252405 is about 272.5788790533.

Adding to 20252405 its reverse (50425202), we get a palindrome (70677607).

The spelling of 20252405 in words is "twenty million, two hundred fifty-two thousand, four hundred five".