21161014512221 has 8 divisors (see below), whose sum is σ = 22455313853760. Its totient is φ = 19897903106752.

The previous prime is 21161014512203. The next prime is 21161014512229. The reversal of 21161014512221 is 12221541016112.

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-21161014512221 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 (21161014512229) 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, 7796982620 + ... + 7796985333.

It is an arithmetic number, because the mean of its divisors is an integer number (2806914231720).

Almost surely, 2^{21161014512221} is an apocalyptic number.

It is an amenable number.

21161014512221 is a deficient number, since it is larger than the sum of its proper divisors (1294299341539).

21161014512221 is a wasteful number, since it uses less digits than its factorization.

21161014512221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15593968035.

The product of its (nonzero) digits is 1920, while the sum is 29.

Adding to 21161014512221 its reverse (12221541016112), we get a palindrome (33382555528333).

The spelling of 21161014512221 in words is "twenty-one trillion, one hundred sixty-one billion, fourteen million, five hundred twelve thousand, two hundred twenty-one".