26091051557 has 4 divisors (see below), whose sum is σ = 26990743020. Its totient is φ = 25191360096.

The previous prime is 26091051533. The next prime is 26091051583. The reversal of 26091051557 is 75515019062.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20804889121 + 5286162436 = 144239^2 + 72706^2 .

It is a cyclic number.

It is not a de Polignac number, because 26091051557 - 2¹⁶ = 26090986021 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 (26091051517) 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, 449845688 + ... + 449845745.

It is an arithmetic number, because the mean of its divisors is an integer number (6747685755).

Almost surely, 2^26091051557 is an apocalyptic number.

It is an amenable number.

26091051557 is a deficient number, since it is larger than the sum of its proper divisors (899691463).

26091051557 is an equidigital number, since it uses as much as digits as its factorization.

26091051557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 899691462.

The product of its (nonzero) digits is 94500, while the sum is 41.

The spelling of 26091051557 in words is "twenty-six billion, ninety-one million, fifty-one thousand, five hundred fifty-seven".