19085747906 has 4 divisors (see below), whose sum is σ = 28628621862. Its totient is φ = 9542873952.

The previous prime is 19085747887. The next prime is 19085747939. The reversal of 19085747906 is 60974758091.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60974758091 = 13 ⋅4690366007.

It can be written as a sum of positive squares in only one way, i.e., 16688764225 + 2396983681 = 129185^2 + 48959^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4771436975 + ... + 4771436978.

Almost surely, 2^19085747906 is an apocalyptic number.

19085747906 is a deficient number, since it is larger than the sum of its proper divisors (9542873956).

19085747906 is an equidigital number, since it uses as much as digits as its factorization.

19085747906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9542873955.

The product of its (nonzero) digits is 3810240, while the sum is 56.

The spelling of 19085747906 in words is "nineteen billion, eighty-five million, seven hundred forty-seven thousand, nine hundred six".