5000665661 has 4 divisors (see below), whose sum is σ = 5001769500. Its totient is φ = 4999561824.

The previous prime is 5000665639. The next prime is 5000665679. The reversal of 5000665661 is 1665660005.

5000665661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1665660005 = 5 ⋅333132001.

It can be written as a sum of positive squares in 2 ways, for example, as 4251822436 + 748843225 = 65206^2 + 27365^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5000665661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5000665261) 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 in 3 ways as a sum of consecutive naturals, for example, 545096 + ... + 554193.

It is an arithmetic number, because the mean of its divisors is an integer number (1250442375).

Almost surely, 2^5000665661 is an apocalyptic number.

It is an amenable number.

5000665661 is a deficient number, since it is larger than the sum of its proper divisors (1103839).

5000665661 is a wasteful number, since it uses less digits than its factorization.

5000665661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1103838.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 5000665661 is about 70715.3848960748. The cubic root of 5000665661 is about 1710.0518275960.

The spelling of 5000665661 in words is "five billion, six hundred sixty-five thousand, six hundred sixty-one".