208688490 has 24 divisors (see below), whose sum is σ = 542590308. Its totient is φ = 55650240.

The previous prime is 208688471. The next prime is 208688521. The reversal of 208688490 is 94886802.

It is a happy number.

208688490 is a `hidden beast` number, since 2 + 0 + 86 + 88 + 490 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 177182721 + 31505769 = 13311^2 + 5613^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1159291 + ... + 1159470.

Almost surely, 2^208688490 is an apocalyptic number.

208688490 is an abundant number, since it is smaller than the sum of its proper divisors (333901818).

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

208688490 is a wasteful number, since it uses less digits than its factorization.

208688490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2318774 (or 2318771 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The square root of 208688490 is about 14446.0544786457. The cubic root of 208688490 is about 593.1522273360.

The spelling of 208688490 in words is "two hundred eight million, six hundred eighty-eight thousand, four hundred ninety".