20819925 has 36 divisors (see below), whose sum is σ = 42621280. Its totient is φ = 9516960.

The previous prime is 20819921. The next prime is 20819933. The reversal of 20819925 is 52991802.

It is not a de Polignac number, because 20819925 - 2² = 20819921 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20819925.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20819921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 5035 + ... + 8184.

Almost surely, 2^20819925 is an apocalyptic number.

20819925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20819925 is an abundant number, since it is smaller than the sum of its proper divisors (21801355).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20819925 is a wasteful number, since it uses less digits than its factorization.

20819925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13242 (or 13234 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 20819925 is about 4562.8856001438. The cubic root of 20819925 is about 275.1015602843.

The spelling of 20819925 in words is "twenty million, eight hundred nineteen thousand, nine hundred twenty-five".