21213343404 has 144 divisors (see below), whose sum is σ = 60017158656. Its totient is φ = 6262550400.

The previous prime is 21213343367. The next prime is 21213343447. The reversal of 21213343404 is 40434331212.

21213343404 is a `hidden beast` number, since 2 + 1 + 213 + 3 + 43 + 404 = 666.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 4222414 + ... + 4227434.

It is an arithmetic number, because the mean of its divisors is an integer number (416785824).

Almost surely, 2^21213343404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21213343404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30008579328).

21213343404 is an abundant number, since it is smaller than the sum of its proper divisors (38803815252).

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

21213343404 is a wasteful number, since it uses less digits than its factorization.

21213343404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5316 (or 5311 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

Adding to 21213343404 its reverse (40434331212), we get a palindrome (61647674616).

The spelling of 21213343404 in words is "twenty-one billion, two hundred thirteen million, three hundred forty-three thousand, four hundred four".