20859284287 has 4 divisors (see below), whose sum is σ = 20894108400. Its totient is φ = 20824460176.

The previous prime is 20859284263. The next prime is 20859284297. The reversal of 20859284287 is 78248295802.

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

It is a cyclic number.

It is not a de Polignac number, because 20859284287 - 2¹⁵ = 20859251519 is a prime.

It is a super-3 number, since 3×20859284287³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20859284297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17411158 + ... + 17412355.

It is an arithmetic number, because the mean of its divisors is an integer number (5223527100).

Almost surely, 2^20859284287 is an apocalyptic number.

20859284287 is a deficient number, since it is larger than the sum of its proper divisors (34824113).

20859284287 is an equidigital number, since it uses as much as digits as its factorization.

20859284287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34824112.

The product of its (nonzero) digits is 5160960, while the sum is 55.

The spelling of 20859284287 in words is "twenty billion, eight hundred fifty-nine million, two hundred eighty-four thousand, two hundred eighty-seven".