1285445309 has 2 divisors, whose sum is σ = 1285445310. Its totient is φ = 1285445308.

The previous prime is 1285445303. The next prime is 1285445351. The reversal of 1285445309 is 9035445821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1142642809 + 142802500 = 33803^2 + 11950^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1285445309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1285445303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642722654 + 642722655.

It is an arithmetic number, because the mean of its divisors is an integer number (642722655).

Almost surely, 2^1285445309 is an apocalyptic number.

It is an amenable number.

1285445309 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285445309 is an equidigital number, since it uses as much as digits as its factorization.

1285445309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 1285445309 is about 35853.1073827639. The cubic root of 1285445309 is about 1087.3045395663.

The spelling of 1285445309 in words is "one billion, two hundred eighty-five million, four hundred forty-five thousand, three hundred nine".