208564989 has 8 divisors (see below), whose sum is σ = 290177472. Its totient is φ = 132997920.

The previous prime is 208564963. The next prime is 208565011. The reversal of 208564989 is 989465802.

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

It is not a de Polignac number, because 208564989 - 2¹³ = 208556797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208564589) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1511272 + ... + 1511409.

It is an arithmetic number, because the mean of its divisors is an integer number (36272184).

Almost surely, 2^208564989 is an apocalyptic number.

It is an amenable number.

208564989 is a deficient number, since it is larger than the sum of its proper divisors (81612483).

208564989 is a wasteful number, since it uses less digits than its factorization.

208564989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3022707.

The product of its (nonzero) digits is 1244160, while the sum is 51.

The square root of 208564989 is about 14441.7792878855. The cubic root of 208564989 is about 593.0351958878.

The spelling of 208564989 in words is "two hundred eight million, five hundred sixty-four thousand, nine hundred eighty-nine".