2001387649 has 2 divisors, whose sum is σ = 2001387650. Its totient is φ = 2001387648.

The previous prime is 2001387601. The next prime is 2001387671. The reversal of 2001387649 is 9467831002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1868400625 + 132987024 = 43225^2 + 11532^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001387649 - 2⁹ = 2001387137 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001387049) 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, 1000693824 + 1000693825.

It is an arithmetic number, because the mean of its divisors is an integer number (1000693825).

Almost surely, 2^2001387649 is an apocalyptic number.

It is an amenable number.

2001387649 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001387649 is an equidigital number, since it uses as much as digits as its factorization.

2001387649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 2001387649 is about 44736.8712473280. The cubic root of 2001387649 is about 1260.2123705609.

The spelling of 2001387649 in words is "two billion, one million, three hundred eighty-seven thousand, six hundred forty-nine".