670649621 has 8 divisors (see below), whose sum is σ = 701573400. Its totient is φ = 640245760.

The previous prime is 670649611. The next prime is 670649657. The reversal of 670649621 is 126946076.

It can be written as a sum of positive squares in 4 ways, for example, as 98596 + 670551025 = 314^2 + 25895^2 .

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

It is not a de Polignac number, because 670649621 - 2⁶ = 670649557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (670649611) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 127340 + ... + 132501.

It is an arithmetic number, because the mean of its divisors is an integer number (87696675).

Almost surely, 2^670649621 is an apocalyptic number.

It is an amenable number.

670649621 is a deficient number, since it is larger than the sum of its proper divisors (30923779).

670649621 is a wasteful number, since it uses less digits than its factorization.

670649621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259959.

The product of its (nonzero) digits is 108864, while the sum is 41.

The square root of 670649621 is about 25896.9036952297. The cubic root of 670649621 is about 875.3167271351.

The spelling of 670649621 in words is "six hundred seventy million, six hundred forty-nine thousand, six hundred twenty-one".