20439999999 has 40 divisors (see below), whose sum is σ = 31375745280. Its totient is φ = 13254514704.

The previous prime is 20439999971. The next prime is 20440000027. The reversal of 20439999999 is 99999993402.

It is an interprime number because it is at equal distance from previous prime (20439999971) and next prime (20440000027).

It is not a de Polignac number, because 20439999999 - 2⁵ = 20439999967 is a prime.

20439999999 is a modest number, since divided by 999999 gives 20439 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20439999199) by changing a digit.

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 39 ways as a sum of consecutive naturals, for example, 604072 + ... + 637010.

It is an arithmetic number, because the mean of its divisors is an integer number (784393632).

Almost surely, 2^20439999999 is an apocalyptic number.

20439999999 is a deficient number, since it is larger than the sum of its proper divisors (10935745281).

20439999999 is a wasteful number, since it uses less digits than its factorization.

20439999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33161 (or 33152 counting only the distinct ones).

The product of its (nonzero) digits is 114791256, while the sum is 72.

The spelling of 20439999999 in words is "twenty billion, four hundred thirty-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".