249075661 has 2 divisors, whose sum is σ = 249075662. Its totient is φ = 249075660.

The previous prime is 249075643. The next prime is 249075677. The reversal of 249075661 is 166570942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 224820036 + 24255625 = 14994^2 + 4925^2 .

It is a cyclic number.

It is not a de Polignac number, because 249075661 - 2²³ = 240687053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (249075611) 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 as a sum of consecutive naturals, namely, 124537830 + 124537831.

It is an arithmetic number, because the mean of its divisors is an integer number (124537831).

Almost surely, 2^249075661 is an apocalyptic number.

It is an amenable number.

249075661 is a deficient number, since it is larger than the sum of its proper divisors (1).

249075661 is an equidigital number, since it uses as much as digits as its factorization.

249075661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 249075661 is about 15782.1310664942. The cubic root of 249075661 is about 629.1831699973.

The spelling of 249075661 in words is "two hundred forty-nine million, seventy-five thousand, six hundred sixty-one".