21109976672736 has 72 divisors (see below), whose sum is σ = 64460821640040. Its totient is φ = 6031421905152.

The previous prime is 21109976672723. The next prime is 21109976672779. The reversal of 21109976672736 is 63727667990112.

It is a super-2 number, since 2×21109976672736² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 2243827851 + ... + 2243837258.

It is an arithmetic number, because the mean of its divisors is an integer number (895289189445).

Almost surely, 2^{21109976672736} is an apocalyptic number.

It is an amenable number.

21109976672736 is an abundant number, since it is smaller than the sum of its proper divisors (43350844967304).

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

21109976672736 is a wasteful number, since it uses less digits than its factorization.

21109976672736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4487665136 (or 4487665121 counting only the distinct ones).

The product of its (nonzero) digits is 72013536, while the sum is 66.

The spelling of 21109976672736 in words is "twenty-one trillion, one hundred nine billion, nine hundred seventy-six million, six hundred seventy-two thousand, seven hundred thirty-six".