21040320321206 has 8 divisors (see below), whose sum is σ = 31754103061944. Its totient is φ = 10455619300560.

The previous prime is 21040320321157. The next prime is 21040320321247. The reversal of 21040320321206 is 60212302304012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×21040320321206³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32270429615 + ... + 32270430266.

It is an arithmetic number, because the mean of its divisors is an integer number (3969262882743).

Almost surely, 2^{21040320321206} is an apocalyptic number.

21040320321206 is a deficient number, since it is larger than the sum of its proper divisors (10713782740738).

21040320321206 is a wasteful number, since it uses less digits than its factorization.

21040320321206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64540860046.

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 21040320321206 its reverse (60212302304012), we get a palindrome (81252622625218).

The spelling of 21040320321206 in words is "twenty-one trillion, forty billion, three hundred twenty million, three hundred twenty-one thousand, two hundred six".