20021321309999 has 4 divisors (see below), whose sum is σ = 20021394462936. Its totient is φ = 20021248157064.

The previous prime is 20021321309993. The next prime is 20021321310013. The reversal of 20021321309999 is 99990312312002.

It is a happy number.

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 20021321309999 - 2²⁴ = 20021304532783 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 (20021321309993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36164384 + ... + 36713829.

It is an arithmetic number, because the mean of its divisors is an integer number (5005348615734).

Almost surely, 2^{20021321309999} is an apocalyptic number.

20021321309999 is a deficient number, since it is larger than the sum of its proper divisors (73152937).

20021321309999 is an equidigital number, since it uses as much as digits as its factorization.

20021321309999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73152936.

The product of its (nonzero) digits is 472392, while the sum is 50.

The spelling of 20021321309999 in words is "twenty trillion, twenty-one billion, three hundred twenty-one million, three hundred nine thousand, nine hundred ninety-nine".