66390312 has 16 divisors (see below), whose sum is σ = 165975840. Its totient is φ = 22130096.

The previous prime is 66390299. The next prime is 66390319. The reversal of 66390312 is 21309366.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 66390312.

It is not an unprimeable number, because it can be changed into a prime (66390319) 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, 1383108 + ... + 1383155.

It is an arithmetic number, because the mean of its divisors is an integer number (10373490).

Almost surely, 2^66390312 is an apocalyptic number.

It is an amenable number.

66390312 is an abundant number, since it is smaller than the sum of its proper divisors (99585528).

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

66390312 is a wasteful number, since it uses less digits than its factorization.

66390312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2766272 (or 2766268 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 30.

The square root of 66390312 is about 8148.0250367804. The cubic root of 66390312 is about 404.9190754331.

Adding to 66390312 its reverse (21309366), we get a palindrome (87699678).

The spelling of 66390312 in words is "sixty-six million, three hundred ninety thousand, three hundred twelve".