26619427661 has 2 divisors, whose sum is σ = 26619427662. Its totient is φ = 26619427660.

The previous prime is 26619427631. The next prime is 26619427669. The reversal of 26619427661 is 16672491662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25483333225 + 1136094436 = 159635^2 + 33706^2 .

It is a cyclic number.

It is not a de Polignac number, because 26619427661 - 2¹⁴ = 26619411277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26619427669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13309713830 + 13309713831.

It is an arithmetic number, because the mean of its divisors is an integer number (13309713831).

Almost surely, 2^26619427661 is an apocalyptic number.

It is an amenable number.

26619427661 is a deficient number, since it is larger than the sum of its proper divisors (1).

26619427661 is an equidigital number, since it uses as much as digits as its factorization.

26619427661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 50.

The spelling of 26619427661 in words is "twenty-six billion, six hundred nineteen million, four hundred twenty-seven thousand, six hundred sixty-one".