165897378 has 12 divisors (see below), whose sum is σ = 359444358. Its totient is φ = 55299120.

The previous prime is 165897377. The next prime is 165897383. The reversal of 165897378 is 873798561.

It can be written as a sum of positive squares in only one way, i.e., 164788569 + 1108809 = 12837^2 + 1053^2 .

It is not an unprimeable number, because it can be changed into a prime (165897377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4608243 + ... + 4608278.

Almost surely, 2^165897378 is an apocalyptic number.

165897378 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

165897378 is an abundant number, since it is smaller than the sum of its proper divisors (193546980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165897378 is a wasteful number, since it uses less digits than its factorization.

165897378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9216529 (or 9216526 counting only the distinct ones).

The product of its digits is 2540160, while the sum is 54.

The square root of 165897378 is about 12880.1156050713. The cubic root of 165897378 is about 549.4731903298.

The spelling of 165897378 in words is "one hundred sixty-five million, eight hundred ninety-seven thousand, three hundred seventy-eight".