21661446111 has 8 divisors (see below), whose sum is σ = 28883447424. Its totient is φ = 14440204440.

The previous prime is 21661446097. The next prime is 21661446113. The reversal of 21661446111 is 11164416612.

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

It is not a de Polignac number, because 21661446111 - 2⁷ = 21661445983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21661446113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 119661 + ... + 240086.

It is an arithmetic number, because the mean of its divisors is an integer number (3610430928).

Almost surely, 2^21661446111 is an apocalyptic number.

21661446111 is a deficient number, since it is larger than the sum of its proper divisors (7222001313).

21661446111 is a wasteful number, since it uses less digits than its factorization.

21661446111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379821.

The product of its digits is 6912, while the sum is 33.

The spelling of 21661446111 in words is "twenty-one billion, six hundred sixty-one million, four hundred forty-six thousand, one hundred eleven".