208428757 has 2 divisors, whose sum is σ = 208428758. Its totient is φ = 208428756.

The previous prime is 208428749. The next prime is 208428761. The reversal of 208428757 is 757824802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204890596 + 3538161 = 14314^2 + 1881^2 .

It is a cyclic number.

It is not a de Polignac number, because 208428757 - 2³ = 208428749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208428257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104214378 + 104214379.

It is an arithmetic number, because the mean of its divisors is an integer number (104214379).

Almost surely, 2^208428757 is an apocalyptic number.

It is an amenable number.

208428757 is a deficient number, since it is larger than the sum of its proper divisors (1).

208428757 is an equidigital number, since it uses as much as digits as its factorization.

208428757 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 250880, while the sum is 43.

The square root of 208428757 is about 14437.0619240897. The cubic root of 208428757 is about 592.9060467466.

The spelling of 208428757 in words is "two hundred eight million, four hundred twenty-eight thousand, seven hundred fifty-seven".