21103444004 has 6 divisors (see below), whose sum is σ = 36931027014. Its totient is φ = 10551722000.

The previous prime is 21103443997. The next prime is 21103444013. The reversal of 21103444004 is 40044430112.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20483334400 + 620109604 = 143120^2 + 24902^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2637930497 + ... + 2637930504.

It is an arithmetic number, because the mean of its divisors is an integer number (6155171169).

Almost surely, 2^21103444004 is an apocalyptic number.

It is an amenable number.

21103444004 is a deficient number, since it is larger than the sum of its proper divisors (15827583010).

21103444004 is a wasteful number, since it uses less digits than its factorization.

21103444004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5275861005 (or 5275861003 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21103444004 its reverse (40044430112), we get a palindrome (61147874116).

The spelling of 21103444004 in words is "twenty-one billion, one hundred three million, four hundred forty-four thousand, four".