664786356 has 48 divisors (see below), whose sum is σ = 1681190784. Its totient is φ = 203239296.

The previous prime is 664786327. The next prime is 664786361. The reversal of 664786356 is 653687466.

It is a junction number, because it is equal to n+sod(n) for n = 664786299 and 664786308.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10921 + ... + 38063.

It is an arithmetic number, because the mean of its divisors is an integer number (35024808).

Almost surely, 2^664786356 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664786356, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (840595392).

664786356 is an abundant number, since it is smaller than the sum of its proper divisors (1016404428).

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

664786356 is a wasteful number, since it uses less digits than its factorization.

664786356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27320 (or 27318 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 51.

The square root of 664786356 is about 25783.4512042124. The cubic root of 664786356 is about 872.7583900403.

The spelling of 664786356 in words is "six hundred sixty-four million, seven hundred eighty-six thousand, three hundred fifty-six".