995995661 has 2 divisors, whose sum is σ = 995995662. Its totient is φ = 995995660.

The previous prime is 995995639. The next prime is 995995687. The reversal of 995995661 is 166599599.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 981631561 + 14364100 = 31331^2 + 3790^2 .

It is an emirp because it is prime and its reverse (166599599) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-995995661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 995995661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (995925661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 497997830 + 497997831.

It is an arithmetic number, because the mean of its divisors is an integer number (497997831).

Almost surely, 2^995995661 is an apocalyptic number.

It is an amenable number.

995995661 is a deficient number, since it is larger than the sum of its proper divisors (1).

995995661 is an equidigital number, since it uses as much as digits as its factorization.

995995661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5904900, while the sum is 59.

The square root of 995995661 is about 31559.3989328061. The cubic root of 995995661 is about 998.6634347225.

The spelling of 995995661 in words is "nine hundred ninety-five million, nine hundred ninety-five thousand, six hundred sixty-one".