26291649609 has 9 divisors (see below), whose sum is σ = 37977529863. Its totient is φ = 17527442112.

The previous prime is 26291649583. The next prime is 26291649641. The reversal of 26291649609 is 90694619262.

It is a happy number.

The square root of 26291649609 is 162147.

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

26291649609 is a `hidden beast` number, since 2 + 6 + 29 + 1 + 6 + 4 + 9 + 609 = 666.

It can be written as a sum of positive squares in only one way, i.e., 25855675209 + 435974400 = 160797^2 + 20880^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is a de Polignac number, because none of the positive numbers 2^k-26291649609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (26291649649) 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, 459417 + ... + 513465.

Almost surely, 2^26291649609 is an apocalyptic number.

26291649609 is the 162147-th square number.

26291649609 is the 81074-th centered octagonal number.

It is an amenable number.

26291649609 is a deficient number, since it is larger than the sum of its proper divisors (11685880254).

26291649609 is an frugal number, since it uses more digits than its factorization.

26291649609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108104 (or 54052 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The spelling of 26291649609 in words is "twenty-six billion, two hundred ninety-one million, six hundred forty-nine thousand, six hundred nine".