20405044739 has 4 divisors (see below), whose sum is σ = 20429839056. Its totient is φ = 20380250424.

The previous prime is 20405044729. The next prime is 20405044811. The reversal of 20405044739 is 93744050402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20405044739 - 2⁸ = 20405044483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20405044729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12395924 + ... + 12397569.

It is an arithmetic number, because the mean of its divisors is an integer number (5107459764).

Almost surely, 2^20405044739 is an apocalyptic number.

20405044739 is a deficient number, since it is larger than the sum of its proper divisors (24794317).

20405044739 is an equidigital number, since it uses as much as digits as its factorization.

20405044739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24794316.

The product of its (nonzero) digits is 120960, while the sum is 38.

The spelling of 20405044739 in words is "twenty billion, four hundred five million, forty-four thousand, seven hundred thirty-nine".