19517892157 has 8 divisors (see below), whose sum is σ = 19755084600. Its totient is φ = 19281561600.

The previous prime is 19517892137. The next prime is 19517892203. The reversal of 19517892157 is 75129871591.

It can be written as a sum of positive squares in 4 ways, for example, as 8233929081 + 11283963076 = 90741^2 + 106226^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 19517892157 - 2¹¹ = 19517890109 is a prime.

It is a super-2 number, since 2×19517892157² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19517892098 and 19517892107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19517892137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169848 + ... + 260545.

It is an arithmetic number, because the mean of its divisors is an integer number (2469385575).

Almost surely, 2^19517892157 is an apocalyptic number.

It is an amenable number.

19517892157 is a deficient number, since it is larger than the sum of its proper divisors (237192443).

19517892157 is a wasteful number, since it uses less digits than its factorization.

19517892157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430943.

The product of its digits is 1587600, while the sum is 55.

The spelling of 19517892157 in words is "nineteen billion, five hundred seventeen million, eight hundred ninety-two thousand, one hundred fifty-seven".