65616665 has 12 divisors (see below), whose sum is σ = 79576164. Its totient is φ = 51941664.

The previous prime is 65616643. The next prime is 65616679. The reversal of 65616665 is 56661656.

It can be written as a sum of positive squares in 2 ways, for example, as 36929929 + 28686736 = 6077^2 + 5356^2 .

It is not a de Polignac number, because 65616665 - 2⁶ = 65616601 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 52427 + ... + 53663.

It is an arithmetic number, because the mean of its divisors is an integer number (6631347).

Almost surely, 2^65616665 is an apocalyptic number.

It is an amenable number.

65616665 is a deficient number, since it is larger than the sum of its proper divisors (13959499).

65616665 is a wasteful number, since it uses less digits than its factorization.

65616665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1448 (or 1345 counting only the distinct ones).

The product of its digits is 194400, while the sum is 41.

The square root of 65616665 is about 8100.4114093051. The cubic root of 65616665 is about 403.3400840494.

The spelling of 65616665 in words is "sixty-five million, six hundred sixteen thousand, six hundred sixty-five".