1605172271 has 2 divisors, whose sum is σ = 1605172272. Its totient is φ = 1605172270.

The previous prime is 1605172237. The next prime is 1605172279. The reversal of 1605172271 is 1722715061.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1605172271 - 2⁶ = 1605172207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1605172279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802586135 + 802586136.

It is an arithmetic number, because the mean of its divisors is an integer number (802586136).

Almost surely, 2^1605172271 is an apocalyptic number.

1605172271 is a deficient number, since it is larger than the sum of its proper divisors (1).

1605172271 is an equidigital number, since it uses as much as digits as its factorization.

1605172271 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5880, while the sum is 32.

The square root of 1605172271 is about 40064.6012210280. The cubic root of 1605172271 is about 1170.8660573347.

The spelling of 1605172271 in words is "one billion, six hundred five million, one hundred seventy-two thousand, two hundred seventy-one".