21244242 has 32 divisors (see below), whose sum is σ = 44939520. Its totient is φ = 6676560.

The previous prime is 21244231. The next prime is 21244243. The reversal of 21244242 is 24244212.

It is not an unprimeable number, because it can be changed into a prime (21244243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37453 + ... + 38015.

It is an arithmetic number, because the mean of its divisors is an integer number (1404360).

Almost surely, 2^21244242 is an apocalyptic number.

21244242 is an abundant number, since it is smaller than the sum of its proper divisors (23695278).

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

21244242 is a wasteful number, since it uses less digits than its factorization.

21244242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 918.

The product of its digits is 1024, while the sum is 21.

The square root of 21244242 is about 4609.1476435454. The cubic root of 21244242 is about 276.9578930466.

Adding to 21244242 its reverse (24244212), we get a palindrome (45488454).

The spelling of 21244242 in words is "twenty-one million, two hundred forty-four thousand, two hundred forty-two".