26205040643 has 4 divisors (see below), whose sum is σ = 27746513640. Its totient is φ = 24663567648.

The previous prime is 26205040591. The next prime is 26205040649. The reversal of 26205040643 is 34604050262.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34604050262 = 2 ⋅17302025131.

It is a cyclic number.

It is not a de Polignac number, because 26205040643 - 2⁸ = 26205040387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26205040649) 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, 770736473 + ... + 770736506.

It is an arithmetic number, because the mean of its divisors is an integer number (6936628410).

Almost surely, 2^26205040643 is an apocalyptic number.

26205040643 is a deficient number, since it is larger than the sum of its proper divisors (1541472997).

26205040643 is a wasteful number, since it uses less digits than its factorization.

26205040643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1541472996.

The product of its (nonzero) digits is 34560, while the sum is 32.

The spelling of 26205040643 in words is "twenty-six billion, two hundred five million, forty thousand, six hundred forty-three".