21668015927 has 8 divisors (see below), whose sum is σ = 23389763040. Its totient is φ = 20011240480.

The previous prime is 21668015923. The next prime is 21668015951. The reversal of 21668015927 is 72951086612.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21668015927 - 2² = 21668015923 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21668015923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16242224 + ... + 16243557.

It is an arithmetic number, because the mean of its divisors is an integer number (2923720380).

Almost surely, 2^21668015927 is an apocalyptic number.

21668015927 is a deficient number, since it is larger than the sum of its proper divisors (1721747113).

21668015927 is a wasteful number, since it uses less digits than its factorization.

21668015927 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32485833.

The product of its (nonzero) digits is 362880, while the sum is 47.

The spelling of 21668015927 in words is "twenty-one billion, six hundred sixty-eight million, fifteen thousand, nine hundred twenty-seven".