26131661 has 2 divisors, whose sum is σ = 26131662. Its totient is φ = 26131660.

The previous prime is 26131643. The next prime is 26131663. The reversal of 26131661 is 16613162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18541636 + 7590025 = 4306^2 + 2755^2 .

It is a cyclic number.

It is not a de Polignac number, because 26131661 - 2¹⁴ = 26115277 is a prime.

Together with 26131663, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1632248 and since 26131661 and 1632248 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 26131661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26131663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13065830 + 13065831.

It is an arithmetic number, because the mean of its divisors is an integer number (13065831).

Almost surely, 2^26131661 is an apocalyptic number.

It is an amenable number.

26131661 is a deficient number, since it is larger than the sum of its proper divisors (1).

26131661 is an equidigital number, since it uses as much as digits as its factorization.

26131661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 26.

The square root of 26131661 is about 5111.9136338557. The cubic root of 26131661 is about 296.7488230709.

The spelling of 26131661 in words is "twenty-six million, one hundred thirty-one thousand, six hundred sixty-one".