668613285 has 56 divisors (see below), whose sum is σ = 1226004984. Its totient is φ = 349764480.

The previous prime is 668613277. The next prime is 668613329. The reversal of 668613285 is 582316866.

668613285 is a `hidden beast` number, since 6 + 6 + 8 + 613 + 28 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 48902049 + 619711236 = 6993^2 + 24894^2 .

It is not a de Polignac number, because 668613285 - 2³ = 668613277 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 668613285.

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 55 ways as a sum of consecutive naturals, for example, 191455 + ... + 194915.

Almost surely, 2^668613285 is an apocalyptic number.

It is an amenable number.

668613285 is a deficient number, since it is larger than the sum of its proper divisors (557391699).

668613285 is an equidigital number, since it uses as much as digits as its factorization.

668613285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3537 (or 3522 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 668613285 is about 25857.5575992784. The cubic root of 668613285 is about 874.4299023807.

The spelling of 668613285 in words is "six hundred sixty-eight million, six hundred thirteen thousand, two hundred eighty-five".