249989689 has 2 divisors, whose sum is σ = 249989690. Its totient is φ = 249989688.

The previous prime is 249989639. The next prime is 249989713. The reversal of 249989689 is 986989942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 179345664 + 70644025 = 13392^2 + 8405^2 .

It is a cyclic number.

It is not a de Polignac number, because 249989689 - 2¹⁷ = 249858617 is a prime.

It is a super-3 number, since 3×249989689³ (a number of 26 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 249989689.

It is not a weakly prime, because it can be changed into another prime (249989629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124994844 + 124994845.

It is an arithmetic number, because the mean of its divisors is an integer number (124994845).

Almost surely, 2^249989689 is an apocalyptic number.

It is an amenable number.

249989689 is a deficient number, since it is larger than the sum of its proper divisors (1).

249989689 is an equidigital number, since it uses as much as digits as its factorization.

249989689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20155392, while the sum is 64.

The square root of 249989689 is about 15811.0622350303. The cubic root of 249989689 is about 629.9518641311.

The spelling of 249989689 in words is "two hundred forty-nine million, nine hundred eighty-nine thousand, six hundred eighty-nine".