21816668097 has 48 divisors (see below), whose sum is σ = 37339694080. Its totient is φ = 12011587200.

The previous prime is 21816668087. The next prime is 21816668099. The reversal of 21816668097 is 79086661812.

It is not a de Polignac number, because 21816668097 - 2¹⁰ = 21816667073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21816668099) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 422847 + ... + 471627.

Almost surely, 2^21816668097 is an apocalyptic number.

It is an amenable number.

21816668097 is a deficient number, since it is larger than the sum of its proper divisors (15523025983).

21816668097 is a wasteful number, since it uses less digits than its factorization.

21816668097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49054 (or 49051 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The spelling of 21816668097 in words is "twenty-one billion, eight hundred sixteen million, six hundred sixty-eight thousand, ninety-seven".