20998825 has 12 divisors (see below), whose sum is σ = 27570780. Its totient is φ = 15810560.

The previous prime is 20998787. The next prime is 20998829. The reversal of 20998825 is 52889902.

It can be written as a sum of positive squares in 6 ways, for example, as 59049 + 20939776 = 243^2 + 4576^2 .

It is not a de Polignac number, because 20998825 - 2¹¹ = 20996777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20998829) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24280 + ... + 25129.

It is an arithmetic number, because the mean of its divisors is an integer number (2297565).

Almost surely, 2^20998825 is an apocalyptic number.

20998825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20998825 is a deficient number, since it is larger than the sum of its proper divisors (6571955).

20998825 is a wasteful number, since it uses less digits than its factorization.

20998825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49436 (or 49431 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 20998825 is about 4582.4474901520. The cubic root of 20998825 is about 275.8872719296.

The spelling of 20998825 in words is "twenty million, nine hundred ninety-eight thousand, eight hundred twenty-five".