20643044139 has 24 divisors (see below), whose sum is σ = 29944738512. Its totient is φ = 13703538240.

The previous prime is 20643044137. The next prime is 20643044143. The reversal of 20643044139 is 93144034602.

It is a happy number.

20643044139 is a `hidden beast` number, since 2 + 0 + 643 + 0 + 4 + 4 + 1 + 3 + 9 = 666.

It is not a de Polignac number, because 20643044139 - 2¹ = 20643044137 is a prime.

It is a super-2 number, since 2×20643044139² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20643044131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2128369 + ... + 2138045.

It is an arithmetic number, because the mean of its divisors is an integer number (1247697438).

Almost surely, 2^20643044139 is an apocalyptic number.

20643044139 is a deficient number, since it is larger than the sum of its proper divisors (9301694373).

20643044139 is a wasteful number, since it uses less digits than its factorization.

20643044139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10667 (or 10664 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The spelling of 20643044139 in words is "twenty billion, six hundred forty-three million, forty-four thousand, one hundred thirty-nine".