21244180 has 24 divisors (see below), whose sum is σ = 46553472. Its totient is φ = 8128032.

The previous prime is 21244177. The next prime is 21244187. The reversal of 21244180 is 8144212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22632 + ... + 23551.

It is an arithmetic number, because the mean of its divisors is an integer number (1939728).

Almost surely, 2^21244180 is an apocalyptic number.

21244180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21244180 is an abundant number, since it is smaller than the sum of its proper divisors (25309292).

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

21244180 is a wasteful number, since it uses less digits than its factorization.

21244180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46215 (or 46213 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 21244180 is about 4609.1409177850. The cubic root of 21244180 is about 276.9576236182.

Adding to 21244180 its reverse (8144212), we get a palindrome (29388392).

It can be divided in two parts, 212441 and 80, that added together give a square (212521 = 461²).

The spelling of 21244180 in words is "twenty-one million, two hundred forty-four thousand, one hundred eighty".