1391641609 has 2 divisors, whose sum is σ = 1391641610. Its totient is φ = 1391641608.

The previous prime is 1391641597. The next prime is 1391641621. The reversal of 1391641609 is 9061461931.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (1391641597) and next prime (1391641621).

It can be written as a sum of positive squares in only one way, i.e., 798232009 + 593409600 = 28253^2 + 24360^2 .

It is a cyclic number.

It is not a de Polignac number, because 1391641609 - 2⁷ = 1391641481 is a prime.

It is not a weakly prime, because it can be changed into another prime (1391641309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695820804 + 695820805.

It is an arithmetic number, because the mean of its divisors is an integer number (695820805).

Almost surely, 2^1391641609 is an apocalyptic number.

It is an amenable number.

1391641609 is a deficient number, since it is larger than the sum of its proper divisors (1).

1391641609 is an equidigital number, since it uses as much as digits as its factorization.

1391641609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 1391641609 is about 37304.7129596248. The cubic root of 1391641609 is about 1116.4582016534.

The spelling of 1391641609 in words is "one billion, three hundred ninety-one million, six hundred forty-one thousand, six hundred nine".