21240202444 has 6 divisors (see below), whose sum is σ = 37170354284. Its totient is φ = 10620101220.

The previous prime is 21240202439. The next prime is 21240202453. The reversal of 21240202444 is 44420204212.

It is a super-2 number, since 2×21240202444² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2655025302 + ... + 2655025309.

Almost surely, 2^21240202444 is an apocalyptic number.

It is an amenable number.

21240202444 is a deficient number, since it is larger than the sum of its proper divisors (15930151840).

21240202444 is a wasteful number, since it uses less digits than its factorization.

21240202444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5310050615 (or 5310050613 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 25.

Adding to 21240202444 its reverse (44420204212), we get a palindrome (65660406656).

The spelling of 21240202444 in words is "twenty-one billion, two hundred forty million, two hundred two thousand, four hundred forty-four".