21442650 has 48 divisors (see below), whose sum is σ = 53565024. Its totient is φ = 5676480.

The previous prime is 21442649. The next prime is 21442657. The reversal of 21442650 is 5624412.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21442650.

It is not an unprimeable number, because it can be changed into a prime (21442657) 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, 24012 + ... + 24888.

It is an arithmetic number, because the mean of its divisors is an integer number (1115938).

Almost surely, 2^21442650 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21442650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26782512).

21442650 is an abundant number, since it is smaller than the sum of its proper divisors (32122374).

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

21442650 is a wasteful number, since it uses less digits than its factorization.

21442650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1055 (or 1050 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 21442650 is about 4630.6209086903. The cubic root of 21442650 is about 277.8174275253.

The spelling of 21442650 in words is "twenty-one million, four hundred forty-two thousand, six hundred fifty".