21225332320524 has 72 divisors (see below), whose sum is σ = 54300633266880. Its totient is φ = 6989702528352.

The previous prime is 21225332320499. The next prime is 21225332320541. The reversal of 21225332320524 is 42502323352212.

21225332320524 is a `hidden beast` number, since 2 + 1 + 2 + 253 + 32 + 320 + 52 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 244097047 + ... + 244183985.

It is an arithmetic number, because the mean of its divisors is an integer number (754175462040).

Almost surely, 2^{21225332320524} is an apocalyptic number.

It is an amenable number.

21225332320524 is an abundant number, since it is smaller than the sum of its proper divisors (33075300946356).

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

21225332320524 is a wasteful number, since it uses less digits than its factorization.

21225332320524 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168739 (or 168734 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 36.

Adding to 21225332320524 its reverse (42502323352212), we get a palindrome (63727655672736).

The spelling of 21225332320524 in words is "twenty-one trillion, two hundred twenty-five billion, three hundred thirty-two million, three hundred twenty thousand, five hundred twenty-four".