21666044043 has 96 divisors (see below), whose sum is σ = 39385906560. Its totient is φ = 11190251520.

The previous prime is 21666044011. The next prime is 21666044069. The reversal of 21666044043 is 34044066612.

It is not a de Polignac number, because 21666044043 - 2⁵ = 21666044011 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21666043989 and 21666044007.

It is not an unprimeable number, because it can be changed into a prime (21666044093) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6116853 + ... + 6120393.

It is an arithmetic number, because the mean of its divisors is an integer number (410269860).

Almost surely, 2^21666044043 is an apocalyptic number.

21666044043 is a deficient number, since it is larger than the sum of its proper divisors (17719862517).

21666044043 is a wasteful number, since it uses less digits than its factorization.

21666044043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3797 (or 3794 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 36.

The spelling of 21666044043 in words is "twenty-one billion, six hundred sixty-six million, forty-four thousand, forty-three".