26531572121 has 4 divisors (see below), whose sum is σ = 28092252852. Its totient is φ = 24970891392.

The previous prime is 26531572079. The next prime is 26531572141. The reversal of 26531572121 is 12127513562.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12127513562 = 2 ⋅6063756781.

It can be written as a sum of positive squares in 2 ways, for example, as 21762150400 + 4769421721 = 147520^2 + 69061^2 .

It is a cyclic number.

It is not a de Polignac number, because 26531572121 - 2⁶ = 26531572057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26531572141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 780340340 + ... + 780340373.

It is an arithmetic number, because the mean of its divisors is an integer number (7023063213).

Almost surely, 2^26531572121 is an apocalyptic number.

It is an amenable number.

26531572121 is a deficient number, since it is larger than the sum of its proper divisors (1560680731).

26531572121 is a wasteful number, since it uses less digits than its factorization.

26531572121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1560680730.

The product of its digits is 25200, while the sum is 35.

The spelling of 26531572121 in words is "twenty-six billion, five hundred thirty-one million, five hundred seventy-two thousand, one hundred twenty-one".