208521490 has 32 divisors (see below), whose sum is σ = 407124144. Its totient is φ = 76584960.

The previous prime is 208521463. The next prime is 208521559. The reversal of 208521490 is 94125802.

It can be written as a sum of positive squares in 8 ways, for example, as 111872929 + 96648561 = 10577^2 + 9831^2 .

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 15 ways as a sum of consecutive naturals, for example, 7989 + ... + 21928.

Almost surely, 2^208521490 is an apocalyptic number.

208521490 is a deficient number, since it is larger than the sum of its proper divisors (198602654).

208521490 is a wasteful number, since it uses less digits than its factorization.

208521490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29982.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 208521490 is about 14440.2731968616. The cubic root of 208521490 is about 592.9939645643.

The spelling of 208521490 in words is "two hundred eight million, five hundred twenty-one thousand, four hundred ninety".