20873420749 has 2 divisors, whose sum is σ = 20873420750. Its totient is φ = 20873420748.

The previous prime is 20873420747. The next prime is 20873420791. The reversal of 20873420749 is 94702437802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20539189225 + 334231524 = 143315^2 + 18282^2 .

It is a cyclic number.

It is not a de Polignac number, because 20873420749 - 2¹ = 20873420747 is a prime.

Together with 20873420747, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 20873420699 and 20873420708.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20873420747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10436710374 + 10436710375.

It is an arithmetic number, because the mean of its divisors is an integer number (10436710375).

Almost surely, 2^20873420749 is an apocalyptic number.

It is an amenable number.

20873420749 is a deficient number, since it is larger than the sum of its proper divisors (1).

20873420749 is an equidigital number, since it uses as much as digits as its factorization.

20873420749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 677376, while the sum is 46.

The spelling of 20873420749 in words is "twenty billion, eight hundred seventy-three million, four hundred twenty thousand, seven hundred forty-nine".