21323404206 has 48 divisors (see below), whose sum is σ = 49788110736. Its totient is φ = 6556629888.

The previous prime is 21323404169. The next prime is 21323404217. The reversal of 21323404206 is 60240432312.

21323404206 is a `hidden beast` number, since 2 + 1 + 3 + 234 + 0 + 420 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21323404206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 326466 + ... + 386298.

It is an arithmetic number, because the mean of its divisors is an integer number (1037252307).

Almost surely, 2^21323404206 is an apocalyptic number.

21323404206 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21323404206 is an abundant number, since it is smaller than the sum of its proper divisors (28464706530).

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

21323404206 is a wasteful number, since it uses less digits than its factorization.

21323404206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61377 (or 61374 counting only the distinct ones).

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

Adding to 21323404206 its reverse (60240432312), we get a palindrome (81563836518).

The spelling of 21323404206 in words is "twenty-one billion, three hundred twenty-three million, four hundred four thousand, two hundred six".