20723657329 has 4 divisors (see below), whose sum is σ = 20723970276. Its totient is φ = 20723344384.

The previous prime is 20723657321. The next prime is 20723657393. The reversal of 20723657329 is 92375632702.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11764656225 + 8959001104 = 108465^2 + 94652^2 .

It is a cyclic number.

It is not a de Polignac number, because 20723657329 - 2³ = 20723657321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20723657321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13744 + ... + 204049.

It is an arithmetic number, because the mean of its divisors is an integer number (5180992569).

Almost surely, 2^20723657329 is an apocalyptic number.

It is an amenable number.

20723657329 is a deficient number, since it is larger than the sum of its proper divisors (312947).

20723657329 is an equidigital number, since it uses as much as digits as its factorization.

20723657329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312946.

The product of its (nonzero) digits is 952560, while the sum is 46.

The spelling of 20723657329 in words is "twenty billion, seven hundred twenty-three million, six hundred fifty-seven thousand, three hundred twenty-nine".