21055350 has 96 divisors (see below), whose sum is σ = 57853440. Its totient is φ = 5040640.

The previous prime is 21055343. The next prime is 21055351. The reversal of 21055350 is 5355012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21055351) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 58471 + ... + 58829.

It is an arithmetic number, because the mean of its divisors is an integer number (602640).

Almost surely, 2^21055350 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21055350, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28926720).

21055350 is an abundant number, since it is smaller than the sum of its proper divisors (36798090).

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

21055350 is a wasteful number, since it uses less digits than its factorization.

21055350 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414 (or 409 counting only the distinct ones).

The product of its (nonzero) digits is 750, while the sum is 21.

The square root of 21055350 is about 4588.6109009154. The cubic root of 21055350 is about 276.1345961869.

The spelling of 21055350 in words is "twenty-one million, fifty-five thousand, three hundred fifty".