21110099966 has 4 divisors (see below), whose sum is σ = 31665149952. Its totient is φ = 10555049982.

The previous prime is 21110099909. The next prime is 21110099971. The reversal of 21110099966 is 66999001112.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5277524990 + ... + 5277524993.

It is an arithmetic number, because the mean of its divisors is an integer number (7916287488).

Almost surely, 2^21110099966 is an apocalyptic number.

21110099966 is a deficient number, since it is larger than the sum of its proper divisors (10555049986).

21110099966 is a wasteful number, since it uses less digits than its factorization.

21110099966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10555049985.

The product of its (nonzero) digits is 52488, while the sum is 44.

The spelling of 21110099966 in words is "twenty-one billion, one hundred ten million, ninety-nine thousand, nine hundred sixty-six".