1640740513 has 2 divisors, whose sum is σ = 1640740514. Its totient is φ = 1640740512.

The previous prime is 1640740471. The next prime is 1640740529. The reversal of 1640740513 is 3150470461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 984202384 + 656538129 = 31372^2 + 25623^2 .

It is an emirp because it is prime and its reverse (3150470461) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640740513 is a prime.

It is not a weakly prime, because it can be changed into another prime (1640740553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820370256 + 820370257.

It is an arithmetic number, because the mean of its divisors is an integer number (820370257).

Almost surely, 2^1640740513 is an apocalyptic number.

It is an amenable number.

1640740513 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640740513 is an equidigital number, since it uses as much as digits as its factorization.

1640740513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 1640740513 is about 40506.0552633801. The cubic root of 1640740513 is about 1179.4511746827.

The spelling of 1640740513 in words is "one billion, six hundred forty million, seven hundred forty thousand, five hundred thirteen".