26909449681 has 9 divisors (see below), whose sum is σ = 27588681169. Its totient is φ = 26246560000.

The previous prime is 26909449669. The next prime is 26909449687. The reversal of 26909449681 is 18694490962.

The square root of 26909449681 is 164041.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 22377467281 + 4531982400 = 149591^2 + 67320^2 .

It is not a de Polignac number, because 26909449681 - 2⁵ = 26909449649 is a prime.

It is a super-2 number, since 2×26909449681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26909449687) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 6723681 + ... + 6727681.

Almost surely, 2^26909449681 is an apocalyptic number.

26909449681 is the 164041-st square number.

26909449681 is the 82021-st centered octagonal number.

It is an amenable number.

26909449681 is a deficient number, since it is larger than the sum of its proper divisors (679231488).

26909449681 is an frugal number, since it uses more digits than its factorization.

26909449681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8084 (or 4042 counting only the distinct ones).

The product of its (nonzero) digits is 6718464, while the sum is 58.

The spelling of 26909449681 in words is "twenty-six billion, nine hundred nine million, four hundred forty-nine thousand, six hundred eighty-one".