21666050436 has 24 divisors (see below), whose sum is σ = 53214861280. Its totient is φ = 6841910592.

The previous prime is 21666050411. The next prime is 21666050467. The reversal of 21666050436 is 63405066612.

It is a junction number, because it is equal to n+sod(n) for n = 21666050394 and 21666050403.

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, 47513041 + ... + 47513496.

Almost surely, 2^21666050436 is an apocalyptic number.

It is an amenable number.

21666050436 is an abundant number, since it is smaller than the sum of its proper divisors (31548810844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21666050436 is a wasteful number, since it uses less digits than its factorization.

21666050436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95026563 (or 95026561 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 39.

The spelling of 21666050436 in words is "twenty-one billion, six hundred sixty-six million, fifty thousand, four hundred thirty-six".