20025909 has 6 divisors (see below), whose sum is σ = 28926326. Its totient is φ = 13350600.

The previous prime is 20025899. The next prime is 20025911. The reversal of 20025909 is 90952002.

It can be written as a sum of positive squares in only one way, i.e., 14976900 + 5049009 = 3870^2 + 2247^2 .

It is not a de Polignac number, because 20025909 - 2⁷ = 20025781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20025919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1112542 + ... + 1112559.

Almost surely, 2^20025909 is an apocalyptic number.

It is an amenable number.

20025909 is a deficient number, since it is larger than the sum of its proper divisors (8900417).

20025909 is a wasteful number, since it uses less digits than its factorization.

20025909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2225107 (or 2225104 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 20025909 is about 4475.0317317311. The cubic root of 20025909 is about 271.5589241580.

The spelling of 20025909 in words is "twenty million, twenty-five thousand, nine hundred nine".