65978165 has 24 divisors (see below), whose sum is σ = 91183968. Its totient is φ = 45444960.

The previous prime is 65978131. The next prime is 65978167. The reversal of 65978165 is 56187956.

It is not a de Polignac number, because 65978165 - 2⁸ = 65977909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65978167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18194 + ... + 21516.

It is an arithmetic number, because the mean of its divisors is an integer number (3799332).

Almost surely, 2^65978165 is an apocalyptic number.

It is an amenable number.

65978165 is a deficient number, since it is larger than the sum of its proper divisors (25205803).

65978165 is a wasteful number, since it uses less digits than its factorization.

65978165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3377 (or 3358 counting only the distinct ones).

The product of its digits is 453600, while the sum is 47.

The square root of 65978165 is about 8122.6944421171. The cubic root of 65978165 is about 404.0794312498.

The spelling of 65978165 in words is "sixty-five million, nine hundred seventy-eight thousand, one hundred sixty-five".