165605025 has 12 divisors (see below), whose sum is σ = 273800432. Its totient is φ = 88322640.

The previous prime is 165605009. The next prime is 165605029. The reversal of 165605025 is 520506561.

It is not a de Polignac number, because 165605025 - 2⁴ = 165605009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165604983 and 165605001.

It is not an unprimeable number, because it can be changed into a prime (165605029) 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 in 11 ways as a sum of consecutive naturals, for example, 1103959 + ... + 1104108.

Almost surely, 2^165605025 is an apocalyptic number.

165605025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165605025 is a deficient number, since it is larger than the sum of its proper divisors (108195407).

165605025 is a wasteful number, since it uses less digits than its factorization.

165605025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2208080 (or 2208075 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 30.

The square root of 165605025 is about 12868.7615954295. The cubic root of 165605025 is about 549.1502304517.

The spelling of 165605025 in words is "one hundred sixty-five million, six hundred five thousand, twenty-five".