20211320999 has 2 divisors, whose sum is σ = 20211321000. Its totient is φ = 20211320998.

The previous prime is 20211320981. The next prime is 20211321019. The reversal of 20211320999 is 99902311202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20211320999 - 2²⁴ = 20194543783 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20217320999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105660499 + 10105660500.

It is an arithmetic number, because the mean of its divisors is an integer number (10105660500).

Almost surely, 2^20211320999 is an apocalyptic number.

20211320999 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211320999 is an equidigital number, since it uses as much as digits as its factorization.

20211320999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 38.

The spelling of 20211320999 in words is "twenty billion, two hundred eleven million, three hundred twenty thousand, nine hundred ninety-nine".