20605561604 has 12 divisors (see below), whose sum is σ = 36075113424. Its totient is φ = 10298386344.

The previous prime is 20605561597. The next prime is 20605561607. The reversal of 20605561604 is 40616550602.

It is not an unprimeable number, because it can be changed into a prime (20605561607) 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, 1088054 + ... + 1106829.

It is an arithmetic number, because the mean of its divisors is an integer number (3006259452).

Almost surely, 2^20605561604 is an apocalyptic number.

It is an amenable number.

20605561604 is a deficient number, since it is larger than the sum of its proper divisors (15469551820).

20605561604 is a wasteful number, since it uses less digits than its factorization.

20605561604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2197234 (or 2197232 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 35.

The spelling of 20605561604 in words is "twenty billion, six hundred five million, five hundred sixty-one thousand, six hundred four".