20323121009 has 2 divisors, whose sum is σ = 20323121010. Its totient is φ = 20323121008.

The previous prime is 20323120997. The next prime is 20323121029. The reversal of 20323121009 is 90012132302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20298270784 + 24850225 = 142472^2 + 4985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20323121009 is a prime.

It is not a weakly prime, because it can be changed into another prime (20323121029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10161560504 + 10161560505.

It is an arithmetic number, because the mean of its divisors is an integer number (10161560505).

Almost surely, 2^20323121009 is an apocalyptic number.

It is an amenable number.

20323121009 is a deficient number, since it is larger than the sum of its proper divisors (1).

20323121009 is an equidigital number, since it uses as much as digits as its factorization.

20323121009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 23.

The spelling of 20323121009 in words is "twenty billion, three hundred twenty-three million, one hundred twenty-one thousand, nine".