21321314340 has 48 divisors (see below), whose sum is σ = 60257639232. Its totient is φ = 5632544896.

The previous prime is 21321314321. The next prime is 21321314351. The reversal of 21321314340 is 4341312312.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21321314340.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1654119 + ... + 1666958.

It is an arithmetic number, because the mean of its divisors is an integer number (1255367484).

Almost surely, 2^21321314340 is an apocalyptic number.

21321314340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21321314340 is an abundant number, since it is smaller than the sum of its proper divisors (38936324892).

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

21321314340 is a wasteful number, since it uses less digits than its factorization.

21321314340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3321196 (or 3321194 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21321314340 its reverse (4341312312), we get a palindrome (25662626652).

The spelling of 21321314340 in words is "twenty-one billion, three hundred twenty-one million, three hundred fourteen thousand, three hundred forty".