1345208561 has 2 divisors, whose sum is σ = 1345208562. Its totient is φ = 1345208560.

The previous prime is 1345208551. The next prime is 1345208633. The reversal of 1345208561 is 1658025431.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 939790336 + 405418225 = 30656^2 + 20135^2 .

It is a cyclic number.

It is not a de Polignac number, because 1345208561 - 2⁶ = 1345208497 is a prime.

It is not a weakly prime, because it can be changed into another prime (1345208551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 672604280 + 672604281.

It is an arithmetic number, because the mean of its divisors is an integer number (672604281).

Almost surely, 2^1345208561 is an apocalyptic number.

It is an amenable number.

1345208561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1345208561 is an equidigital number, since it uses as much as digits as its factorization.

1345208561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28800, while the sum is 35.

The square root of 1345208561 is about 36677.0849577771. The cubic root of 1345208561 is about 1103.9003579752.

The spelling of 1345208561 in words is "one billion, three hundred forty-five million, two hundred eight thousand, five hundred sixty-one".