21001801680006 has 64 divisors (see below), whose sum is σ = 49262297043456. Its totient is φ = 5843762323200.

The previous prime is 21001801679993. The next prime is 21001801680011. The reversal of 21001801680006 is 60008610810012.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 9861925 + ... + 11800896.

It is an arithmetic number, because the mean of its divisors is an integer number (769723391304).

Almost surely, 2^{21001801680006} is an apocalyptic number.

21001801680006 is an abundant number, since it is smaller than the sum of its proper divisors (28260495363450).

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

21001801680006 is a wasteful number, since it uses less digits than its factorization.

21001801680006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21663437.

The product of its (nonzero) digits is 4608, while the sum is 33.

The spelling of 21001801680006 in words is "twenty-one trillion, one billion, eight hundred one million, six hundred eighty thousand, six".