665701216 has 12 divisors (see below), whose sum is σ = 1310599332. Its totient is φ = 332850592.

The previous prime is 665701199. The next prime is 665701217. The reversal of 665701216 is 612107566.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665701217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10401550 + ... + 10401613.

It is an arithmetic number, because the mean of its divisors is an integer number (109216611).

Almost surely, 2^665701216 is an apocalyptic number.

It is an amenable number.

665701216 is a deficient number, since it is larger than the sum of its proper divisors (644898116).

665701216 is a wasteful number, since it uses less digits than its factorization.

665701216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20803173 (or 20803165 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 665701216 is about 25801.1863293144. The cubic root of 665701216 is about 873.1585615863.

The spelling of 665701216 in words is "six hundred sixty-five million, seven hundred one thousand, two hundred sixteen".