21235320312 has 32 divisors (see below), whose sum is σ = 54523122000. Its totient is φ = 6887130624.

The previous prime is 21235320307. The next prime is 21235320319. The reversal of 21235320312 is 21302353212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21235320319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11955937 + ... + 11957712.

Almost surely, 2^21235320312 is an apocalyptic number.

It is an amenable number.

21235320312 is an abundant number, since it is smaller than the sum of its proper divisors (33287801688).

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

21235320312 is a wasteful number, since it uses less digits than its factorization.

21235320312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23913695 (or 23913691 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

Adding to 21235320312 its reverse (21302353212), we get a palindrome (42537673524).

The spelling of 21235320312 in words is "twenty-one billion, two hundred thirty-five million, three hundred twenty thousand, three hundred twelve".