665678426238 has 48 divisors (see below), whose sum is σ = 1656158714496. Its totient is φ = 189292435920.

The previous prime is 665678426227. The next prime is 665678426263. The reversal of 665678426238 is 832624876566.

It is a happy number.

665678426238 is a `hidden beast` number, since 6 + 6 + 567 + 8 + 4 + 2 + 62 + 3 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12492756 + ... + 12545927.

It is an arithmetic number, because the mean of its divisors is an integer number (34503306552).

Almost surely, 2^665678426238 is an apocalyptic number.

665678426238 is an abundant number, since it is smaller than the sum of its proper divisors (990480288258).

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

665678426238 is a wasteful number, since it uses less digits than its factorization.

665678426238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25038909 (or 25038906 counting only the distinct ones).

The product of its digits is 139345920, while the sum is 63.

The spelling of 665678426238 in words is "six hundred sixty-five billion, six hundred seventy-eight million, four hundred twenty-six thousand, two hundred thirty-eight".