1289261 has 2 divisors, whose sum is σ = 1289262. Its totient is φ = 1289260.

The previous prime is 1289237. The next prime is 1289273. The reversal of 1289261 is 1629821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 866761 + 422500 = 931^2 + 650^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1289261 is a prime.

It is a super-2 number, since 2×1289261² = 3324387852242, which contains 22 as substring.

It is equal to p₉₉₂₈₁ and since 1289261 and 99281 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1289231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 644630 + 644631.

It is an arithmetic number, because the mean of its divisors is an integer number (644631).

2^1289261 is an apocalyptic number.

It is an amenable number.

1289261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1289261 is an equidigital number, since it uses as much as digits as its factorization.

1289261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 29.

The square root of 1289261 is about 1135.4562959445. The cubic root of 1289261 is about 108.8379321403.

The spelling of 1289261 in words is "one million, two hundred eighty-nine thousand, two hundred sixty-one".