21013102144 has 42 divisors (see below), whose sum is σ = 44295013010. Its totient is φ = 9888509952.

The previous prime is 21013102133. The next prime is 21013102157. The reversal of 21013102144 is 44120131012.

It can be written as a sum of positive squares in 3 ways, for example, as 4142209600 + 16870892544 = 64360^2 + 129888^2 .

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 549549 + ... + 586540.

Almost surely, 2^21013102144 is an apocalyptic number.

It is an amenable number.

21013102144 is an abundant number, since it is smaller than the sum of its proper divisors (23281910866).

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

21013102144 is a wasteful number, since it uses less digits than its factorization.

21013102144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1136135 (or 1136108 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21013102144 its reverse (44120131012), we get a palindrome (65133233156).

The spelling of 21013102144 in words is "twenty-one billion, thirteen million, one hundred two thousand, one hundred forty-four".