191078261 has 8 divisors (see below), whose sum is σ = 209602848. Its totient is φ = 172746000.

The previous prime is 191078221. The next prime is 191078281. The reversal of 191078261 is 162870191.

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 191078261 - 2¹⁸ = 190816117 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 (191078221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45995 + ... + 49976.

It is an arithmetic number, because the mean of its divisors is an integer number (26200356).

Almost surely, 2^191078261 is an apocalyptic number.

191078261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

191078261 is a deficient number, since it is larger than the sum of its proper divisors (18524587).

191078261 is a wasteful number, since it uses less digits than its factorization.

191078261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96163.

The product of its (nonzero) digits is 6048, while the sum is 35.

The square root of 191078261 is about 13823.1060547187. The cubic root of 191078261 is about 575.9751679190.

The spelling of 191078261 in words is "one hundred ninety-one million, seventy-eight thousand, two hundred sixty-one".