208640670 has 32 divisors (see below), whose sum is σ = 572272128. Its totient is φ = 47689248.

The previous prime is 208640657. The next prime is 208640681. The reversal of 208640670 is 76046802.

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 15 ways as a sum of consecutive naturals, for example, 496554 + ... + 496973.

It is an arithmetic number, because the mean of its divisors is an integer number (17883504).

Almost surely, 2^208640670 is an apocalyptic number.

208640670 is an abundant number, since it is smaller than the sum of its proper divisors (363631458).

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

208640670 is a wasteful number, since it uses less digits than its factorization.

208640670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 993544.

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 208640670 is about 14444.3992606131. The cubic root of 208640670 is about 593.1069178473.

The spelling of 208640670 in words is "two hundred eight million, six hundred forty thousand, six hundred seventy".