19718648356 has 18 divisors (see below), whose sum is σ = 37929880310. Its totient is φ = 8963021760.

The previous prime is 19718648353. The next prime is 19718648377. The reversal of 19718648356 is 65384681791.

It can be written as a sum of positive squares in only one way, i.e., 16546705956 + 3171942400 = 128634^2 + 56320^2 .

It is a super-3 number, since 3×19718648356³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19718648356.

It is not an unprimeable number, because it can be changed into a prime (19718648353) 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, 20370021 + ... + 20370988.

Almost surely, 2^19718648356 is an apocalyptic number.

It is an amenable number.

19718648356 is a deficient number, since it is larger than the sum of its proper divisors (18211231954).

19718648356 is a wasteful number, since it uses less digits than its factorization.

19718648356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40741035 (or 40741022 counting only the distinct ones).

The product of its digits is 8709120, while the sum is 58.

It can be divided in two parts, 197186 and 48356, that added together give a palindrome (245542).

The spelling of 19718648356 in words is "nineteen billion, seven hundred eighteen million, six hundred forty-eight thousand, three hundred fifty-six".