165340403 has 4 divisors (see below), whose sum is σ = 165477480. Its totient is φ = 165203328.

The previous prime is 165340393. The next prime is 165340421. The reversal of 165340403 is 304043561.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 165340403 - 2⁴ = 165340387 is a prime.

It is a super-4 number, since 4×165340403⁴ (a number of 34 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165340433) 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 3 ways as a sum of consecutive naturals, for example, 66713 + ... + 69146.

It is an arithmetic number, because the mean of its divisors is an integer number (41369370).

Almost surely, 2^165340403 is an apocalyptic number.

165340403 is a deficient number, since it is larger than the sum of its proper divisors (137077).

165340403 is a wasteful number, since it uses less digits than its factorization.

165340403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137076.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 165340403 is about 12858.4759205747. The cubic root of 165340403 is about 548.8575768877.

Adding to 165340403 its reverse (304043561), we get a palindrome (469383964).

The spelling of 165340403 in words is "one hundred sixty-five million, three hundred forty thousand, four hundred three".