21193406207999 has 4 divisors (see below), whose sum is σ = 21193422164400. Its totient is φ = 21193390251600.

The previous prime is 21193406207969. The next prime is 21193406208011. The reversal of 21193406207999 is 99970260439112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21193406207999 - 2²⁴ = 21193389430783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21193406207969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5784902 + ... + 8709299.

It is an arithmetic number, because the mean of its divisors is an integer number (5298355541100).

Almost surely, 2^{21193406207999} is an apocalyptic number.

21193406207999 is a deficient number, since it is larger than the sum of its proper divisors (15956401).

21193406207999 is a wasteful number, since it uses less digits than its factorization.

21193406207999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15956400.

The product of its (nonzero) digits is 13226976, while the sum is 62.

The spelling of 21193406207999 in words is "twenty-one trillion, one hundred ninety-three billion, four hundred six million, two hundred seven thousand, nine hundred ninety-nine".