21605546611231 has 8 divisors (see below), whose sum is σ = 24956139401424. Its totient is φ = 18486029185920.

The previous prime is 21605546611223. The next prime is 21605546611279. The reversal of 21605546611231 is 13211664550612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21605546611231 - 2³ = 21605546611223 is a prime.

It is a super-2 number, since 2×21605546611231² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21605546614231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57768841020 + ... + 57768841393.

It is an arithmetic number, because the mean of its divisors is an integer number (3119517425178).

Almost surely, 2^{21605546611231} is an apocalyptic number.

21605546611231 is a deficient number, since it is larger than the sum of its proper divisors (3350592790193).

21605546611231 is a wasteful number, since it uses less digits than its factorization.

21605546611231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115537682441.

The product of its (nonzero) digits is 259200, while the sum is 43.

The spelling of 21605546611231 in words is "twenty-one trillion, six hundred five billion, five hundred forty-six million, six hundred eleven thousand, two hundred thirty-one".