21256044514277 has 2 divisors, whose sum is σ = 21256044514278. Its totient is φ = 21256044514276.

The previous prime is 21256044514253. The next prime is 21256044514291. The reversal of 21256044514277 is 77241544065212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18989601582436 + 2266442931841 = 4357706^2 + 1505471^2 .

It is a cyclic number.

It is not a de Polignac number, because 21256044514277 - 2¹⁴ = 21256044497893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21256044514217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10628022257138 + 10628022257139.

It is an arithmetic number, because the mean of its divisors is an integer number (10628022257139).

Almost surely, 2^{21256044514277} is an apocalyptic number.

It is an amenable number.

21256044514277 is a deficient number, since it is larger than the sum of its proper divisors (1).

21256044514277 is an equidigital number, since it uses as much as digits as its factorization.

21256044514277 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3763200, while the sum is 50.

Adding to 21256044514277 its reverse (77241544065212), we get a palindrome (98497588579489).

The spelling of 21256044514277 in words is "twenty-one trillion, two hundred fifty-six billion, forty-four million, five hundred fourteen thousand, two hundred seventy-seven".