20502775747 has 4 divisors (see below), whose sum is σ = 20505623080. Its totient is φ = 20499928416.

The previous prime is 20502775681. The next prime is 20502775751. The reversal of 20502775747 is 74757720502.

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 20502775747 - 2³¹ = 18355292099 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20502775697 and 20502775706.

It is not an unprimeable number, because it can be changed into a prime (20502775247) 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, 1412838 + ... + 1427275.

It is an arithmetic number, because the mean of its divisors is an integer number (5126405770).

Almost surely, 2^20502775747 is an apocalyptic number.

20502775747 is a deficient number, since it is larger than the sum of its proper divisors (2847333).

20502775747 is an equidigital number, since it uses as much as digits as its factorization.

20502775747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2847332.

The product of its (nonzero) digits is 960400, while the sum is 46.

The spelling of 20502775747 in words is "twenty billion, five hundred two million, seven hundred seventy-five thousand, seven hundred forty-seven".