21243411124 has 24 divisors (see below), whose sum is σ = 40084504488. Its totient is φ = 9792689280.

The previous prime is 21243411109. The next prime is 21243411227. The reversal of 21243411124 is 42111434212.

It can be written as a sum of positive squares in 4 ways, for example, as 588547600 + 20654863524 = 24260^2 + 143718^2 .

It is a congruent number.

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, 206107 + ... + 291490.

It is an arithmetic number, because the mean of its divisors is an integer number (1670187687).

Almost surely, 2^21243411124 is an apocalyptic number.

It is an amenable number.

21243411124 is a deficient number, since it is larger than the sum of its proper divisors (18841093364).

21243411124 is a wasteful number, since it uses less digits than its factorization.

21243411124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 498435 (or 498433 counting only the distinct ones).

The product of its digits is 1536, while the sum is 25.

Adding to 21243411124 its reverse (42111434212), we get a palindrome (63354845336).

The spelling of 21243411124 in words is "twenty-one billion, two hundred forty-three million, four hundred eleven thousand, one hundred twenty-four".