20980640347 has 4 divisors (see below), whose sum is σ = 21074724160. Its totient is φ = 20886556536.

The previous prime is 20980640297. The next prime is 20980640363. The reversal of 20980640347 is 74304608902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74304608902 = 2 ⋅37152304451.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20980640347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20980640147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47041572 + ... + 47042017.

It is an arithmetic number, because the mean of its divisors is an integer number (5268681040).

Almost surely, 2^20980640347 is an apocalyptic number.

20980640347 is a deficient number, since it is larger than the sum of its proper divisors (94083813).

20980640347 is an equidigital number, since it uses as much as digits as its factorization.

20980640347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94083812.

The product of its (nonzero) digits is 290304, while the sum is 43.

The spelling of 20980640347 in words is "twenty billion, nine hundred eighty million, six hundred forty thousand, three hundred forty-seven".