171220151 has 2 divisors, whose sum is σ = 171220152. Its totient is φ = 171220150.

The previous prime is 171220103. The next prime is 171220163. The reversal of 171220151 is 151022171.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 171220151 - 2⁶ = 171220087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171220171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85610075 + 85610076.

It is an arithmetic number, because the mean of its divisors is an integer number (85610076).

Almost surely, 2^171220151 is an apocalyptic number.

171220151 is a deficient number, since it is larger than the sum of its proper divisors (1).

171220151 is an equidigital number, since it uses as much as digits as its factorization.

171220151 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 140, while the sum is 20.

The square root of 171220151 is about 13085.1118069354. Note that the first 3 decimals coincide. The cubic root of 171220151 is about 555.2880046207.

The spelling of 171220151 in words is "one hundred seventy-one million, two hundred twenty thousand, one hundred fifty-one".