66864361 has 4 divisors (see below), whose sum is σ = 67203972. Its totient is φ = 66524752.

The previous prime is 66864341. The next prime is 66864367. The reversal of 66864361 is 16346866.

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

It can be written as a sum of positive squares in 2 ways, for example, as 64304361 + 2560000 = 8019^2 + 1600^2 .

It is a cyclic number.

It is not a de Polignac number, because 66864361 - 2¹³ = 66856169 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (66864367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169510 + ... + 169903.

It is an arithmetic number, because the mean of its divisors is an integer number (16800993).

Almost surely, 2^66864361 is an apocalyptic number.

It is an amenable number.

66864361 is a deficient number, since it is larger than the sum of its proper divisors (339611).

66864361 is a wasteful number, since it uses less digits than its factorization.

66864361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 339610.

The product of its digits is 124416, while the sum is 40.

The square root of 66864361 is about 8177.0631035843. The cubic root of 66864361 is about 405.8805431275.

The spelling of 66864361 in words is "sixty-six million, eight hundred sixty-four thousand, three hundred sixty-one".