165770 has 24 divisors (see below), whose sum is σ = 330372. Its totient is φ = 59840.

The previous prime is 165749. The next prime is 165779. The reversal of 165770 is 77561.

165770 = T₂₅₅ + T₂₅₆ + ... + T₂₅₉.

It can be written as a sum of positive squares in 2 ways, for example, as 165649 + 121 = 407^2 + 11^2 .

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (165779) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1142 + ... + 1278.

2¹⁶⁵⁷⁷⁰ is an apocalyptic number.

165770 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

165770 is a deficient number, since it is larger than the sum of its proper divisors (164602).

165770 is a wasteful number, since it uses less digits than its factorization.

165770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 1470, while the sum is 26.

The square root of 165770 is about 407.1486215131. The cubic root of 165770 is about 54.9332523616.

Subtracting from 165770 its reverse (77561), we obtain a square (88209 = 297²).

The spelling of 165770 in words is "one hundred sixty-five thousand, seven hundred seventy".