665638930 has 32 divisors (see below), whose sum is σ = 1318664448. Its totient is φ = 239904000.

The previous prime is 665638889. The next prime is 665638933. The reversal of 665638930 is 39836566.

It is not an unprimeable number, because it can be changed into a prime (665638933) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14346 + ... + 39205.

It is an arithmetic number, because the mean of its divisors is an integer number (41208264).

Almost surely, 2^665638930 is an apocalyptic number.

665638930 is a deficient number, since it is larger than the sum of its proper divisors (653025518).

665638930 is a wasteful number, since it uses less digits than its factorization.

665638930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53682.

The product of its (nonzero) digits is 699840, while the sum is 46.

The square root of 665638930 is about 25799.9792635576. The cubic root of 665638930 is about 873.1313285228.

The spelling of 665638930 in words is "six hundred sixty-five million, six hundred thirty-eight thousand, nine hundred thirty".