655773661 has 2 divisors, whose sum is σ = 655773662. Its totient is φ = 655773660.

The previous prime is 655773637. The next prime is 655773683. The reversal of 655773661 is 166377556.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 561974436 + 93799225 = 23706^2 + 9685^2 .

It is a cyclic number.

It is not a de Polignac number, because 655773661 - 2⁹ = 655773149 is a prime.

It is a super-2 number, since 2×655773661² = 860078188922685842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (655773061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327886830 + 327886831.

It is an arithmetic number, because the mean of its divisors is an integer number (327886831).

Almost surely, 2^655773661 is an apocalyptic number.

It is an amenable number.

655773661 is a deficient number, since it is larger than the sum of its proper divisors (1).

655773661 is an equidigital number, since it uses as much as digits as its factorization.

655773661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 793800, while the sum is 46.

The square root of 655773661 is about 25608.0780418992. The cubic root of 655773661 is about 868.7963541955.

The spelling of 655773661 in words is "six hundred fifty-five million, seven hundred seventy-three thousand, six hundred sixty-one".