21611457269 has 2 divisors, whose sum is σ = 21611457270. Its totient is φ = 21611457268.

The previous prime is 21611457253. The next prime is 21611457311. The reversal of 21611457269 is 96275411612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21359822500 + 251634769 = 146150^2 + 15863^2 .

It is a cyclic number.

It is not a de Polignac number, because 21611457269 - 2⁴ = 21611457253 is a prime.

It is a super-2 number, since 2×21611457269² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21611427269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10805728634 + 10805728635.

It is an arithmetic number, because the mean of its divisors is an integer number (10805728635).

Almost surely, 2^21611457269 is an apocalyptic number.

It is an amenable number.

21611457269 is a deficient number, since it is larger than the sum of its proper divisors (1).

21611457269 is an equidigital number, since it uses as much as digits as its factorization.

21611457269 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 44.

The spelling of 21611457269 in words is "twenty-one billion, six hundred eleven million, four hundred fifty-seven thousand, two hundred sixty-nine".