21100970944 has 56 divisors (see below), whose sum is σ = 43111044080. Its totient is φ = 10239768576.

The previous prime is 21100970941. The next prime is 21100971007. The reversal of 21100970944 is 44907900112.

It is a super-2 number, since 2×21100970944² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100970941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 957619 + ... + 979405.

Almost surely, 2^21100970944 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100970944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21555522040).

21100970944 is an abundant number, since it is smaller than the sum of its proper divisors (22010073136).

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

21100970944 is a wasteful number, since it uses less digits than its factorization.

21100970944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22245 (or 22235 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 37.

The spelling of 21100970944 in words is "twenty-one billion, one hundred million, nine hundred seventy thousand, nine hundred forty-four".