21525223124 has 48 divisors (see below), whose sum is σ = 38306256912. Its totient is φ = 10582720512.

The previous prime is 21525223123. The next prime is 21525223133. The reversal of 21525223124 is 42132252512.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 13192819600 + 8332403524 = 114860^2 + 91282^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21525223123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31794674 + ... + 31795350.

It is an arithmetic number, because the mean of its divisors is an integer number (798047019).

Almost surely, 2^21525223124 is an apocalyptic number.

It is an amenable number.

21525223124 is a deficient number, since it is larger than the sum of its proper divisors (16781033788).

21525223124 is a wasteful number, since it uses less digits than its factorization.

21525223124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1292 (or 1290 counting only the distinct ones).

The product of its digits is 9600, while the sum is 29.

Adding to 21525223124 its reverse (42132252512), we get a palindrome (63657475636).

The spelling of 21525223124 in words is "twenty-one billion, five hundred twenty-five million, two hundred twenty-three thousand, one hundred twenty-four".