26439729561 has 16 divisors (see below), whose sum is σ = 44765680000. Its totient is φ = 15108416784.

The previous prime is 26439729541. The next prime is 26439729571. The reversal of 26439729561 is 16592793462.

26439729561 is a `hidden beast` number, since 2 + 6 + 4 + 3 + 9 + 72 + 9 + 561 = 666.

It is not a de Polignac number, because 26439729561 - 2²² = 26435535257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 26439729498 and 26439729507.

It is not an unprimeable number, because it can be changed into a prime (26439729541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69946186 + ... + 69946563.

It is an arithmetic number, because the mean of its divisors is an integer number (2797855000).

Almost surely, 2^26439729561 is an apocalyptic number.

26439729561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

26439729561 is a deficient number, since it is larger than the sum of its proper divisors (18325950439).

26439729561 is a wasteful number, since it uses less digits than its factorization.

26439729561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139892765 (or 139892759 counting only the distinct ones).

The product of its digits is 4898880, while the sum is 54.

The spelling of 26439729561 in words is "twenty-six billion, four hundred thirty-nine million, seven hundred twenty-nine thousand, five hundred sixty-one".