21131232321004 has 48 divisors (see below), whose sum is σ = 41564707144128. Its totient is φ = 9326824075008.

The previous prime is 21131232320953. The next prime is 21131232321037. The reversal of 21131232321004 is 40012323213112.

It is a self number, because there is not a number n which added to its sum of digits gives 21131232321004.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3640714 + ... + 7450990.

It is an arithmetic number, because the mean of its divisors is an integer number (865931398836).

Almost surely, 2^{21131232321004} is an apocalyptic number.

It is an amenable number.

21131232321004 is a deficient number, since it is larger than the sum of its proper divisors (20433474823124).

21131232321004 is a wasteful number, since it uses less digits than its factorization.

21131232321004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3814954 (or 3814952 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

Adding to 21131232321004 its reverse (40012323213112), we get a palindrome (61143555534116).

The spelling of 21131232321004 in words is "twenty-one trillion, one hundred thirty-one billion, two hundred thirty-two million, three hundred twenty-one thousand, four".