21605546611145 has 8 divisors (see below), whose sum is σ = 29630463923904. Its totient is φ = 14815231961904.

The previous prime is 21605546611069. The next prime is 21605546611151. The reversal of 21605546611145 is 54111664550612.

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 21605546611145 - 2³⁰ = 21604472869321 is a prime.

It is a super-2 number, since 2×21605546611145² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21605546611145.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 308650665839 + ... + 308650665908.

It is an arithmetic number, because the mean of its divisors is an integer number (3703807990488).

Almost surely, 2^{21605546611145} is an apocalyptic number.

It is an amenable number.

21605546611145 is a deficient number, since it is larger than the sum of its proper divisors (8024917312759).

21605546611145 is an equidigital number, since it uses as much as digits as its factorization.

21605546611145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 617301331759.

The product of its (nonzero) digits is 864000, while the sum is 47.

The spelling of 21605546611145 in words is "twenty-one trillion, six hundred five billion, five hundred forty-six million, six hundred eleven thousand, one hundred forty-five".