665678390 has 32 divisors (see below), whose sum is σ = 1317859200. Its totient is φ = 240557184.

The previous prime is 665678389. The next prime is 665678413. The reversal of 665678390 is 93876566.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48365 + ... + 60584.

It is an arithmetic number, because the mean of its divisors is an integer number (41183100).

Almost surely, 2^665678390 is an apocalyptic number.

665678390 is a deficient number, since it is larger than the sum of its proper divisors (652180810).

665678390 is a wasteful number, since it uses less digits than its factorization.

665678390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109016.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The square root of 665678390 is about 25800.7439815212. The cubic root of 665678390 is about 873.1485816611.

The spelling of 665678390 in words is "six hundred sixty-five million, six hundred seventy-eight thousand, three hundred ninety".