21252243044 has 12 divisors (see below), whose sum is σ = 37193462124. Its totient is φ = 10625539584.

The previous prime is 21252243029. The next prime is 21252243059. The reversal of 21252243044 is 44034225212.

It is an interprime number because it is at equal distance from previous prime (21252243029) and next prime (21252243059).

It can be written as a sum of positive squares in 2 ways, for example, as 11985870400 + 9266372644 = 109480^2 + 96262^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21252242998 and 21252243016.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57389 + ... + 214004.

It is an arithmetic number, because the mean of its divisors is an integer number (3099455177).

Almost surely, 2^21252243044 is an apocalyptic number.

It is an amenable number.

21252243044 is a deficient number, since it is larger than the sum of its proper divisors (15941219080).

21252243044 is a wasteful number, since it uses less digits than its factorization.

21252243044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290974 (or 290972 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 29.

Adding to 21252243044 its reverse (44034225212), we get a palindrome (65286468256).

The spelling of 21252243044 in words is "twenty-one billion, two hundred fifty-two million, two hundred forty-three thousand, forty-four".