208495981 has 2 divisors, whose sum is σ = 208495982. Its totient is φ = 208495980.

The previous prime is 208495979. The next prime is 208496021. The reversal of 208495981 is 189594802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 185885956 + 22610025 = 13634^2 + 4755^2 .

It is a cyclic number.

It is not a de Polignac number, because 208495981 - 2¹ = 208495979 is a prime.

It is a super-2 number, since 2×208495981² = 86941148186304722, which contains 22 as substring.

Together with 208495979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208495921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104247990 + 104247991.

It is an arithmetic number, because the mean of its divisors is an integer number (104247991).

Almost surely, 2^208495981 is an apocalyptic number.

It is an amenable number.

208495981 is a deficient number, since it is larger than the sum of its proper divisors (1).

208495981 is an equidigital number, since it uses as much as digits as its factorization.

208495981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 46.

The square root of 208495981 is about 14439.3899109346. The cubic root of 208495981 is about 592.9697827243.

The spelling of 208495981 in words is "two hundred eight million, four hundred ninety-five thousand, nine hundred eighty-one".