19915108018 has 8 divisors (see below), whose sum is σ = 32170559148. Its totient is φ = 9191588304.

The previous prime is 19915108013. The next prime is 19915108033. The reversal of 19915108018 is 81080151991.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14076161449 + 5838946569 = 118643^2 + 76413^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×19915108018² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19915108013) 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, 382982821 + ... + 382982872.

Almost surely, 2^19915108018 is an apocalyptic number.

19915108018 is a deficient number, since it is larger than the sum of its proper divisors (12255451130).

19915108018 is a wasteful number, since it uses less digits than its factorization.

19915108018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 765965708.

The product of its (nonzero) digits is 25920, while the sum is 43.

The spelling of 19915108018 in words is "nineteen billion, nine hundred fifteen million, one hundred eight thousand, eighteen".