21611167761005 has 16 divisors (see below), whose sum is σ = 26359948306224. Its totient is φ = 17004599854080.

The previous prime is 21611167760971. The next prime is 21611167761011. The reversal of 21611167761005 is 50016776111612.

It can be written as a sum of positive squares in 8 ways, for example, as 495185245636 + 21115982515369 = 703694^2 + 4595213^2 .

It is not a de Polignac number, because 21611167761005 - 2¹⁰ = 21611167759981 is a prime.

It is a super-2 number, since 2×21611167761005² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3848309 + ... + 7617861.

It is an arithmetic number, because the mean of its divisors is an integer number (1647496769139).

Almost surely, 2^{21611167761005} is an apocalyptic number.

It is an amenable number.

21611167761005 is a deficient number, since it is larger than the sum of its proper divisors (4748780545219).

21611167761005 is a wasteful number, since it uses less digits than its factorization.

21611167761005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3788416.

The product of its (nonzero) digits is 105840, while the sum is 44.

The spelling of 21611167761005 in words is "twenty-one trillion, six hundred eleven billion, one hundred sixty-seven million, seven hundred sixty-one thousand, five".