670991065 has 8 divisors (see below), whose sum is σ = 811067400. Its totient is φ = 532874112.

The previous prime is 670991059. The next prime is 670991081. The reversal of 670991065 is 560199076.

It can be written as a sum of positive squares in 4 ways, for example, as 32114889 + 638876176 = 5667^2 + 25276^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 670991065 - 2⁹ = 670990553 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 489090 + ... + 490459.

It is an arithmetic number, because the mean of its divisors is an integer number (101383425).

Almost surely, 2^670991065 is an apocalyptic number.

It is an amenable number.

670991065 is a deficient number, since it is larger than the sum of its proper divisors (140076335).

670991065 is a wasteful number, since it uses less digits than its factorization.

670991065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 979691.

The product of its (nonzero) digits is 102060, while the sum is 43.

The square root of 670991065 is about 25903.4952274785. The cubic root of 670991065 is about 875.4652502629.

The spelling of 670991065 in words is "six hundred seventy million, nine hundred ninety-one thousand, sixty-five".