20807497859 has 4 divisors (see below), whose sum is σ = 21369862704. Its totient is φ = 20245133016.

The previous prime is 20807497853. The next prime is 20807497891. The reversal of 20807497859 is 95879470802.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20807497859 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20807497798 and 20807497807.

It is not an unprimeable number, because it can be changed into a prime (20807497853) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 281182367 + ... + 281182440.

It is an arithmetic number, because the mean of its divisors is an integer number (5342465676).

Almost surely, 2^20807497859 is an apocalyptic number.

20807497859 is a deficient number, since it is larger than the sum of its proper divisors (562364845).

20807497859 is an equidigital number, since it uses as much as digits as its factorization.

20807497859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562364844.

The product of its (nonzero) digits is 10160640, while the sum is 59.

The spelling of 20807497859 in words is "twenty billion, eight hundred seven million, four hundred ninety-seven thousand, eight hundred fifty-nine".