21606205611115 has 8 divisors (see below), whose sum is σ = 25928853879600. Its totient is φ = 17284026391392.

The previous prime is 21606205611077. The next prime is 21606205611127. The reversal of 21606205611115 is 51111650260612.

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 21606205611115 - 2¹⁹ = 21606205086827 is a prime.

It is a super-2 number, since 2×21606205611115² (a number of 27 digits) contains 22 as substring.

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, 117160840 + ... + 117345109.

It is an arithmetic number, because the mean of its divisors is an integer number (3241106734950).

Almost surely, 2^{21606205611115} is an apocalyptic number.

21606205611115 is a deficient number, since it is larger than the sum of its proper divisors (4322648268485).

21606205611115 is a wasteful number, since it uses less digits than its factorization.

21606205611115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234524381.

The product of its (nonzero) digits is 21600, while the sum is 37.

Adding to 21606205611115 its reverse (51111650260612), we get a palindrome (72717855871727).

The spelling of 21606205611115 in words is "twenty-one trillion, six hundred six billion, two hundred five million, six hundred eleven thousand, one hundred fifteen".