21850528 has 24 divisors (see below), whose sum is σ = 49164192. Its totient is φ = 9364416.

The previous prime is 21850489. The next prime is 21850547. The reversal of 21850528 is 82505812.

It is a self number, because there is not a number n which added to its sum of digits gives 21850528.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 48550 + ... + 48997.

It is an arithmetic number, because the mean of its divisors is an integer number (2048508).

Almost surely, 2^21850528 is an apocalyptic number.

21850528 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21850528 is an abundant number, since it is smaller than the sum of its proper divisors (27313664).

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

21850528 is an equidigital number, since it uses as much as digits as its factorization.

21850528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97564 (or 97556 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 31.

The square root of 21850528 is about 4674.4548345235. The cubic root of 21850528 is about 279.5679049640.

The spelling of 21850528 in words is "twenty-one million, eight hundred fifty thousand, five hundred twenty-eight".