23209773721 has 2 divisors, whose sum is σ = 23209773722. Its totient is φ = 23209773720.

The previous prime is 23209773679. The next prime is 23209773737. The reversal of 23209773721 is 12737790232.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17669055625 + 5540718096 = 132925^2 + 74436^2 .

It is a cyclic number.

It is not a de Polignac number, because 23209773721 - 2¹³ = 23209765529 is a prime.

It is not a weakly prime, because it can be changed into another prime (23209773791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11604886860 + 11604886861.

It is an arithmetic number, because the mean of its divisors is an integer number (11604886861).

Almost surely, 2^23209773721 is an apocalyptic number.

It is an amenable number.

23209773721 is a deficient number, since it is larger than the sum of its proper divisors (1).

23209773721 is an equidigital number, since it uses as much as digits as its factorization.

23209773721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 222264, while the sum is 43.

The spelling of 23209773721 in words is "twenty-three billion, two hundred nine million, seven hundred seventy-three thousand, seven hundred twenty-one".