2165350661 has 2 divisors, whose sum is σ = 2165350662. Its totient is φ = 2165350660.

The previous prime is 2165350619. The next prime is 2165350679. The reversal of 2165350661 is 1660535612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1273133761 + 892216900 = 35681^2 + 29870^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2165350661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2365350661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1082675330 + 1082675331.

It is an arithmetic number, because the mean of its divisors is an integer number (1082675331).

Almost surely, 2^2165350661 is an apocalyptic number.

It is an amenable number.

2165350661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2165350661 is an equidigital number, since it uses as much as digits as its factorization.

2165350661 is an evil number, because the sum of its binary digits is even.

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

The square root of 2165350661 is about 46533.3284968956. The cubic root of 2165350661 is about 1293.7273088477.

The spelling of 2165350661 in words is "two billion, one hundred sixty-five million, three hundred fifty thousand, six hundred sixty-one".