20651656775 has 12 divisors (see below), whose sum is σ = 25652919864. Its totient is φ = 16492380000.

The previous prime is 20651656771. The next prime is 20651656777. The reversal of 20651656775 is 57765615602.

It is not a de Polignac number, because 20651656775 - 2² = 20651656771 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20651656771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 709076 + ... + 737625.

It is an arithmetic number, because the mean of its divisors is an integer number (2137743322).

Almost surely, 2^20651656775 is an apocalyptic number.

20651656775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20651656775 is a deficient number, since it is larger than the sum of its proper divisors (5001263089).

20651656775 is a wasteful number, since it uses less digits than its factorization.

20651656775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1447282 (or 1447277 counting only the distinct ones).

The product of its (nonzero) digits is 2646000, while the sum is 50.

The spelling of 20651656775 in words is "twenty billion, six hundred fifty-one million, six hundred fifty-six thousand, seven hundred seventy-five".