21144440234 has 16 divisors (see below), whose sum is σ = 33635601216. Its totient is φ = 9934545600.

The previous prime is 21144440171. The next prime is 21144440243. The reversal of 21144440234 is 43204444112.

It is a junction number, because it is equal to n+sod(n) for n = 21144440197 and 21144440206.

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, 471332 + ... + 514239.

It is an arithmetic number, because the mean of its divisors is an integer number (2102225076).

Almost surely, 2^21144440234 is an apocalyptic number.

21144440234 is a deficient number, since it is larger than the sum of its proper divisors (12491160982).

21144440234 is a wasteful number, since it uses less digits than its factorization.

21144440234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 986221.

The product of its (nonzero) digits is 12288, while the sum is 29.

Adding to 21144440234 its reverse (43204444112), we get a palindrome (64348884346).

The spelling of 21144440234 in words is "twenty-one billion, one hundred forty-four million, four hundred forty thousand, two hundred thirty-four".