20448161729 has 4 divisors (see below), whose sum is σ = 20452313520. Its totient is φ = 20444009940.

The previous prime is 20448161687. The next prime is 20448161749. The reversal of 20448161729 is 92716184402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92716184402 = 2 ⋅46358092201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20448161729 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20448161729.

It is not an unprimeable number, because it can be changed into a prime (20448161749) 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 in 3 ways as a sum of consecutive naturals, for example, 2068499 + ... + 2078360.

It is an arithmetic number, because the mean of its divisors is an integer number (5113078380).

Almost surely, 2^20448161729 is an apocalyptic number.

It is an amenable number.

20448161729 is a deficient number, since it is larger than the sum of its proper divisors (4151791).

20448161729 is an equidigital number, since it uses as much as digits as its factorization.

20448161729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4151790.

The product of its (nonzero) digits is 193536, while the sum is 44.

The spelling of 20448161729 in words is "twenty billion, four hundred forty-eight million, one hundred sixty-one thousand, seven hundred twenty-nine".