26273561221 has 2 divisors, whose sum is σ = 26273561222. Its totient is φ = 26273561220.

The previous prime is 26273561189. The next prime is 26273561243. The reversal of 26273561221 is 12216537262.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23205952225 + 3067608996 = 152335^2 + 55386^2 .

It is a cyclic number.

It is not a de Polignac number, because 26273561221 - 2⁵ = 26273561189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26273561261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13136780610 + 13136780611.

It is an arithmetic number, because the mean of its divisors is an integer number (13136780611).

Almost surely, 2^26273561221 is an apocalyptic number.

It is an amenable number.

26273561221 is a deficient number, since it is larger than the sum of its proper divisors (1).

26273561221 is an equidigital number, since it uses as much as digits as its factorization.

26273561221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 37.

The spelling of 26273561221 in words is "twenty-six billion, two hundred seventy-three million, five hundred sixty-one thousand, two hundred twenty-one".