21100100044 has 24 divisors (see below), whose sum is σ = 37083564000. Its totient is φ = 10504851840.

The previous prime is 21100100033. The next prime is 21100100057. The reversal of 21100100044 is 44000100112.

It is a junction number, because it is equal to n+sod(n) for n = 21100099997 and 21100100033.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1735017 + ... + 1747135.

It is an arithmetic number, because the mean of its divisors is an integer number (1545148500).

Almost surely, 2^21100100044 is an apocalyptic number.

It is an amenable number.

21100100044 is a deficient number, since it is larger than the sum of its proper divisors (15983463956).

21100100044 is a wasteful number, since it uses less digits than its factorization.

21100100044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13953 (or 13951 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21100100044 its reverse (44000100112), we get a palindrome (65100200156).

The spelling of 21100100044 in words is "twenty-one billion, one hundred million, one hundred thousand, forty-four".