1290426509 has 2 divisors, whose sum is σ = 1290426510. Its totient is φ = 1290426508.

The previous prime is 1290426461. The next prime is 1290426551. The reversal of 1290426509 is 9056240921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1232712100 + 57714409 = 35110^2 + 7597^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1290426509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1290426559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645213254 + 645213255.

It is an arithmetic number, because the mean of its divisors is an integer number (645213255).

Almost surely, 2^1290426509 is an apocalyptic number.

It is an amenable number.

1290426509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1290426509 is an equidigital number, since it uses as much as digits as its factorization.

1290426509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 1290426509 is about 35922.5069977027. The cubic root of 1290426509 is about 1088.7071923916.

The spelling of 1290426509 in words is "one billion, two hundred ninety million, four hundred twenty-six thousand, five hundred nine".