208511990 has 16 divisors (see below), whose sum is σ = 375535440. Its totient is φ = 83357280.

The previous prime is 208511977. The next prime is 208511993. The reversal of 208511990 is 99115802.

It is a self number, because there is not a number n which added to its sum of digits gives 208511990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208511993) 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, 16541 + ... + 26279.

It is an arithmetic number, because the mean of its divisors is an integer number (23470965).

Almost surely, 2^208511990 is an apocalyptic number.

208511990 is a deficient number, since it is larger than the sum of its proper divisors (167023450).

208511990 is a wasteful number, since it uses less digits than its factorization.

208511990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11887.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 208511990 is about 14439.9442519700. The cubic root of 208511990 is about 592.9849590525.

The spelling of 208511990 in words is "two hundred eight million, five hundred eleven thousand, nine hundred ninety".