21312420132 has 24 divisors (see below), whose sum is σ = 49731718176. Its totient is φ = 7103748928.

The previous prime is 21312420121. The next prime is 21312420133. The reversal of 21312420132 is 23102421312.

It is a junction number, because it is equal to n+sod(n) for n = 21312420099 and 21312420108.

It is not an unprimeable number, because it can be changed into a prime (21312420133) 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 7 ways as a sum of consecutive naturals, for example, 252448 + ... + 326120.

It is an arithmetic number, because the mean of its divisors is an integer number (2072154924).

Almost surely, 2^21312420132 is an apocalyptic number.

It is an amenable number.

21312420132 is an abundant number, since it is smaller than the sum of its proper divisors (28419298044).

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

21312420132 is a wasteful number, since it uses less digits than its factorization.

21312420132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97787 (or 97785 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21312420132 its reverse (23102421312), we get a palindrome (44414841444).

The spelling of 21312420132 in words is "twenty-one billion, three hundred twelve million, four hundred twenty thousand, one hundred thirty-two".