191131057 has 6 divisors (see below), whose sum is σ = 206964582. Its totient is φ = 176428512.

The previous prime is 191131033. The next prime is 191131069. The reversal of 191131057 is 750131191.

It can be written as a sum of positive squares in 3 ways, for example, as 4016016 + 187115041 = 2004^2 + 13679^2 .

It is not a de Polignac number, because 191131057 - 2¹¹ = 191129009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191131007) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 565308 + ... + 565645.

It is an arithmetic number, because the mean of its divisors is an integer number (34494097).

Almost surely, 2^191131057 is an apocalyptic number.

It is an amenable number.

191131057 is a deficient number, since it is larger than the sum of its proper divisors (15833525).

191131057 is a wasteful number, since it uses less digits than its factorization.

191131057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1130979 (or 1130966 counting only the distinct ones).

The product of its (nonzero) digits is 945, while the sum is 28.

The square root of 191131057 is about 13825.0156238610. The cubic root of 191131057 is about 576.0282114285.

The spelling of 191131057 in words is "one hundred ninety-one million, one hundred thirty-one thousand, fifty-seven".