21252343124 has 48 divisors (see below), whose sum is σ = 38778503568. Its totient is φ = 10181956608.

The previous prime is 21252343121. The next prime is 21252343159. The reversal of 21252343124 is 42134325212.

It can be written as a sum of positive squares in 8 ways, for example, as 1995230224 + 19257112900 = 44668^2 + 138770^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21252343121) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 10770602 + ... + 10772574.

It is an arithmetic number, because the mean of its divisors is an integer number (807885491).

Almost surely, 2^21252343124 is an apocalyptic number.

It is an amenable number.

21252343124 is a deficient number, since it is larger than the sum of its proper divisors (17526160444).

21252343124 is a wasteful number, since it uses less digits than its factorization.

21252343124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3084 (or 3082 counting only the distinct ones).

The product of its digits is 11520, while the sum is 29.

Adding to 21252343124 its reverse (42134325212), we get a palindrome (63386668336).

The spelling of 21252343124 in words is "twenty-one billion, two hundred fifty-two million, three hundred forty-three thousand, one hundred twenty-four".