6611645639 has 2 divisors, whose sum is σ = 6611645640. Its totient is φ = 6611645638.

The previous prime is 6611645603. The next prime is 6611645657. The reversal of 6611645639 is 9365461166.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6611645639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6611645593 and 6611645602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6611645839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3305822819 + 3305822820.

It is an arithmetic number, because the mean of its divisors is an integer number (3305822820).

Almost surely, 2^6611645639 is an apocalyptic number.

6611645639 is a deficient number, since it is larger than the sum of its proper divisors (1).

6611645639 is an equidigital number, since it uses as much as digits as its factorization.

6611645639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 699840, while the sum is 47.

The square root of 6611645639 is about 81312.0264106116. The cubic root of 6611645639 is about 1876.8800710970.

The spelling of 6611645639 in words is "six billion, six hundred eleven million, six hundred forty-five thousand, six hundred thirty-nine".