21042211144 has 8 divisors (see below), whose sum is σ = 39454145910. Its totient is φ = 10521105568.

The previous prime is 21042211087. The next prime is 21042211163. The reversal of 21042211144 is 44111224012.

It can be written as a sum of positive squares in only one way, i.e., 20949088644 + 93122500 = 144738^2 + 9650^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1315138189 + ... + 1315138204.

Almost surely, 2^21042211144 is an apocalyptic number.

It is an amenable number.

21042211144 is a deficient number, since it is larger than the sum of its proper divisors (18411934766).

21042211144 is a wasteful number, since it uses less digits than its factorization.

21042211144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2630276399 (or 2630276395 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21042211144 its reverse (44111224012), we get a palindrome (65153435156).

The spelling of 21042211144 in words is "twenty-one billion, forty-two million, two hundred eleven thousand, one hundred forty-four".