20643240244 has 48 divisors (see below), whose sum is σ = 40633266240. Its totient is φ = 9093980160.

The previous prime is 20643240203. The next prime is 20643240257. The reversal of 20643240244 is 44204234602.

It is a super-2 number, since 2×20643240244² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 393727 + ... + 443065.

It is an arithmetic number, because the mean of its divisors is an integer number (846526380).

Almost surely, 2^20643240244 is an apocalyptic number.

It is an amenable number.

20643240244 is a deficient number, since it is larger than the sum of its proper divisors (19990025996).

20643240244 is a wasteful number, since it uses less digits than its factorization.

20643240244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49648 (or 49646 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 31.

Adding to 20643240244 its reverse (44204234602), we get a palindrome (64847474846).

The spelling of 20643240244 in words is "twenty billion, six hundred forty-three million, two hundred forty thousand, two hundred forty-four".