21632550 has 48 divisors (see below), whose sum is σ = 55509840. Its totient is φ = 5568640.

The previous prime is 21632537. The next prime is 21632557. The reversal of 21632550 is 5523612.

It is a self number, because there is not a number n which added to its sum of digits gives 21632550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21632557) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1864 + ... + 6836.

It is an arithmetic number, because the mean of its divisors is an integer number (1156455).

Almost surely, 2^21632550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21632550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27754920).

21632550 is an abundant number, since it is smaller than the sum of its proper divisors (33877290).

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

21632550 is a wasteful number, since it uses less digits than its factorization.

21632550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5017 (or 5012 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 21632550 is about 4651.0805196212. The cubic root of 21632550 is about 278.6351521357.

The spelling of 21632550 in words is "twenty-one million, six hundred thirty-two thousand, five hundred fifty".