2661661365 has 32 divisors (see below), whose sum is σ = 4649463936. Its totient is φ = 1289487360.

The previous prime is 2661661309. The next prime is 2661661391. The reversal of 2661661365 is 5631661662.

It is not a de Polignac number, because 2661661365 - 2⁷ = 2661661237 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 230817 + ... + 242073.

It is an arithmetic number, because the mean of its divisors is an integer number (145295748).

Almost surely, 2^2661661365 is an apocalyptic number.

It is an amenable number.

2661661365 is a deficient number, since it is larger than the sum of its proper divisors (1987802571).

2661661365 is a wasteful number, since it uses less digits than its factorization.

2661661365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12709.

The product of its digits is 233280, while the sum is 42.

The square root of 2661661365 is about 51591.2915616580. The cubic root of 2661661365 is about 1385.8543847111.

The spelling of 2661661365 in words is "two billion, six hundred sixty-one million, six hundred sixty-one thousand, three hundred sixty-five".