20457759565 has 32 divisors (see below), whose sum is σ = 25866449280. Its totient is φ = 15510722304.

The previous prime is 20457759551. The next prime is 20457759571. The reversal of 20457759565 is 56595775402.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20457759565 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2842902 + ... + 2850088.

It is an arithmetic number, because the mean of its divisors is an integer number (808326540).

Almost surely, 2^20457759565 is an apocalyptic number.

It is an amenable number.

20457759565 is a deficient number, since it is larger than the sum of its proper divisors (5408689715).

20457759565 is a wasteful number, since it uses less digits than its factorization.

20457759565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7581.

The product of its (nonzero) digits is 13230000, while the sum is 55.

The spelling of 20457759565 in words is "twenty billion, four hundred fifty-seven million, seven hundred fifty-nine thousand, five hundred sixty-five".