21899025 has 24 divisors (see below), whose sum is σ = 40230560. Its totient is φ = 11679120.

The previous prime is 21899023. The next prime is 21899047. The reversal of 21899025 is 52099812.

It is not a de Polignac number, because 21899025 - 2¹ = 21899023 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21899023) 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 23 ways as a sum of consecutive naturals, for example, 15547 + ... + 16896.

Almost surely, 2^21899025 is an apocalyptic number.

21899025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21899025 is a deficient number, since it is larger than the sum of its proper divisors (18331535).

21899025 is a wasteful number, since it uses less digits than its factorization.

21899025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32462 (or 32451 counting only the distinct ones).

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

The square root of 21899025 is about 4679.6394091853. The cubic root of 21899025 is about 279.7745847336.

The spelling of 21899025 in words is "twenty-one million, eight hundred ninety-nine thousand, twenty-five".