20426105647 has 4 divisors (see below), whose sum is σ = 20434538160. Its totient is φ = 20417673136.

The previous prime is 20426105599. The next prime is 20426105681. The reversal of 20426105647 is 74650162402.

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 20426105647 - 2¹⁵ = 20426072879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20426100647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4212622 + ... + 4217467.

It is an arithmetic number, because the mean of its divisors is an integer number (5108634540).

Almost surely, 2^20426105647 is an apocalyptic number.

20426105647 is a deficient number, since it is larger than the sum of its proper divisors (8432513).

20426105647 is an equidigital number, since it uses as much as digits as its factorization.

20426105647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8432512.

The product of its (nonzero) digits is 80640, while the sum is 37.

The spelling of 20426105647 in words is "twenty billion, four hundred twenty-six million, one hundred five thousand, six hundred forty-seven".