20603690765 has 12 divisors (see below), whose sum is σ = 28761070716. Its totient is φ = 14128244928.

The previous prime is 20603690761. The next prime is 20603690777. The reversal of 20603690765 is 56709630602.

It can be written as a sum of positive squares in 2 ways, for example, as 10904789476 + 9698901289 = 104426^2 + 98483^2 .

It is not a de Polignac number, because 20603690765 - 2² = 20603690761 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20603690761) 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 11 ways as a sum of consecutive naturals, for example, 42048104 + ... + 42048593.

It is an arithmetic number, because the mean of its divisors is an integer number (2396755893).

Almost surely, 2^20603690765 is an apocalyptic number.

It is an amenable number.

20603690765 is a deficient number, since it is larger than the sum of its proper divisors (8157379951).

20603690765 is an equidigital number, since it uses as much as digits as its factorization.

20603690765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84096716 (or 84096709 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 44.

The spelling of 20603690765 in words is "twenty billion, six hundred three million, six hundred ninety thousand, seven hundred sixty-five".