191261530647 has 18 divisors (see below), whose sum is σ = 303665003096. Its totient is φ = 115916078520.

The previous prime is 191261530619. The next prime is 191261530657. The reversal of 191261530647 is 746035162191.

191261530647 is a `hidden beast` number, since 1 + 9 + 12 + 61 + 530 + 6 + 47 = 666.

It is not a de Polignac number, because 191261530647 - 2¹⁵ = 191261497879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191261530657) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 87814123 + ... + 87816300.

Almost surely, 2^191261530647 is an apocalyptic number.

191261530647 is a deficient number, since it is larger than the sum of its proper divisors (112403472449).

191261530647 is a wasteful number, since it uses less digits than its factorization.

191261530647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175630451 (or 175630437 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The spelling of 191261530647 in words is "one hundred ninety-one billion, two hundred sixty-one million, five hundred thirty thousand, six hundred forty-seven".