191555904241 has 27 divisors (see below), whose sum is σ = 209836392033. Its totient is φ = 174788290560.

The previous prime is 191555904229. The next prime is 191555904247. The reversal of 191555904241 is 142409555191.

The square root of 191555904241 is 437671.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 13623791841 + 177932112400 = 116721^2 + 421820^2 .

It is not a de Polignac number, because 191555904241 - 2³⁵ = 157196165873 is a prime.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 191555904191 and 191555904200.

It is not an unprimeable number, because it can be changed into a prime (191555904247) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 745353585 + ... + 745353841.

Almost surely, 2^191555904241 is an apocalyptic number.

191555904241 is the 437671-st square number.

191555904241 is the 218836-th centered octagonal number.

It is an amenable number.

191555904241 is a deficient number, since it is larger than the sum of its proper divisors (18280487792).

191555904241 is an frugal number, since it uses more digits than its factorization.

191555904241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 802 (or 401 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 46.

The spelling of 191555904241 in words is "one hundred ninety-one billion, five hundred fifty-five million, nine hundred four thousand, two hundred forty-one".