19918717153 has 6 divisors (see below), whose sum is σ = 20581984482. Its totient is φ = 19276176960.

The previous prime is 19918717111. The next prime is 19918717201. The reversal of 19918717153 is 35171781991.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16257015009 + 3661702144 = 127503^2 + 60512^2 .

It is not a de Polignac number, because 19918717153 - 2¹³ = 19918708961 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 19918717153.

It is not an unprimeable number, because it can be changed into a prime (19918717253) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10362576 + ... + 10364497.

It is an arithmetic number, because the mean of its divisors is an integer number (3430330747).

Almost surely, 2^19918717153 is an apocalyptic number.

It is an amenable number.

19918717153 is a deficient number, since it is larger than the sum of its proper divisors (663267329).

19918717153 is an equidigital number, since it uses as much as digits as its factorization.

19918717153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20727135 (or 20727104 counting only the distinct ones).

The product of its digits is 476280, while the sum is 52.

The spelling of 19918717153 in words is "nineteen billion, nine hundred eighteen million, seven hundred seventeen thousand, one hundred fifty-three".