21040045244 has 24 divisors (see below), whose sum is σ = 36991020528. Its totient is φ = 10471294080.

The previous prime is 21040045237. The next prime is 21040045277. The reversal of 21040045244 is 44254004012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 763799 + ... + 790865.

It is an arithmetic number, because the mean of its divisors is an integer number (1541292522).

Almost surely, 2^21040045244 is an apocalyptic number.

It is an amenable number.

21040045244 is a deficient number, since it is larger than the sum of its proper divisors (15950975284).

21040045244 is a wasteful number, since it uses less digits than its factorization.

21040045244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27965 (or 27963 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 26.

Adding to 21040045244 its reverse (44254004012), we get a palindrome (65294049256).

The spelling of 21040045244 in words is "twenty-one billion, forty million, forty-five thousand, two hundred forty-four".