21160668546845 has 8 divisors (see below), whose sum is σ = 25392844289976. Its totient is φ = 16928506814976.

The previous prime is 21160668546827. The next prime is 21160668546847. The reversal of 21160668546845 is 54864586606112.

It can be written as a sum of positive squares in 4 ways, for example, as 71504364409 + 21089164182436 = 267403^2 + 4592294^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21160668546845 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21160668546847) 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, 169829 + ... + 6507701.

It is an arithmetic number, because the mean of its divisors is an integer number (3174105536247).

Almost surely, 2^{21160668546845} is an apocalyptic number.

It is an amenable number.

21160668546845 is a deficient number, since it is larger than the sum of its proper divisors (4232175743131).

21160668546845 is an equidigital number, since it uses as much as digits as its factorization.

21160668546845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7005631.

The product of its (nonzero) digits is 66355200, while the sum is 62.

The spelling of 21160668546845 in words is "twenty-one trillion, one hundred sixty billion, six hundred sixty-eight million, five hundred forty-six thousand, eight hundred forty-five".