19729781153 has 4 divisors (see below), whose sum is σ = 19736456340. Its totient is φ = 19723105968.

The previous prime is 19729781147. The next prime is 19729781161. The reversal of 19729781153 is 35118792791.

It is a happy number.

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 980503969 + 18749277184 = 31313^2 + 136928^2 .

It is a cyclic number.

It is not a de Polignac number, because 19729781153 - 2²² = 19725586849 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19729781095 and 19729781104.

It is not an unprimeable number, because it can be changed into a prime (19729781653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3333158 + ... + 3339071.

It is an arithmetic number, because the mean of its divisors is an integer number (4934114085).

Almost surely, 2^19729781153 is an apocalyptic number.

It is an amenable number.

19729781153 is a deficient number, since it is larger than the sum of its proper divisors (6675187).

19729781153 is an equidigital number, since it uses as much as digits as its factorization.

19729781153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6675186.

The product of its digits is 952560, while the sum is 53.

The spelling of 19729781153 in words is "nineteen billion, seven hundred twenty-nine million, seven hundred eighty-one thousand, one hundred fifty-three".