21661004646832 has 20 divisors (see below), whose sum is σ = 42400858325896. Its totient is φ = 10718847659520.

The previous prime is 21661004646821. The next prime is 21661004646863. The reversal of 21661004646832 is 23864640016612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6978414894 + ... + 6978417997.

Almost surely, 2^{21661004646832} is an apocalyptic number.

It is an amenable number.

21661004646832 is a deficient number, since it is larger than the sum of its proper divisors (20739853679064).

21661004646832 is a wasteful number, since it uses less digits than its factorization.

21661004646832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13956832996 (or 13956832990 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 49.

The spelling of 21661004646832 in words is "twenty-one trillion, six hundred sixty-one billion, four million, six hundred forty-six thousand, eight hundred thirty-two".