171091951 has 2 divisors, whose sum is σ = 171091952. Its totient is φ = 171091950.

The previous prime is 171091913. The next prime is 171091981. The reversal of 171091951 is 159190171.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 171091951 - 2¹¹ = 171089903 is a prime.

It is equal to p_9560734 and since 171091951 and 9560734 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171091981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85545975 + 85545976.

It is an arithmetic number, because the mean of its divisors is an integer number (85545976).

Almost surely, 2^171091951 is an apocalyptic number.

171091951 is a deficient number, since it is larger than the sum of its proper divisors (1).

171091951 is an equidigital number, since it uses as much as digits as its factorization.

171091951 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2835, while the sum is 34.

The square root of 171091951 is about 13080.2121924684. The cubic root of 171091951 is about 555.1493805621.

The spelling of 171091951 in words is "one hundred seventy-one million, ninety-one thousand, nine hundred fifty-one".