655983389 has 2 divisors, whose sum is σ = 655983390. Its totient is φ = 655983388.

The previous prime is 655983353. The next prime is 655983431. The reversal of 655983389 is 983389556.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 632120164 + 23863225 = 25142^2 + 4885^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-655983389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (655983319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327991694 + 327991695.

It is an arithmetic number, because the mean of its divisors is an integer number (327991695).

Almost surely, 2^655983389 is an apocalyptic number.

It is an amenable number.

655983389 is a deficient number, since it is larger than the sum of its proper divisors (1).

655983389 is an equidigital number, since it uses as much as digits as its factorization.

655983389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6998400, while the sum is 56.

The square root of 655983389 is about 25612.1726723837. The cubic root of 655983389 is about 868.8889631302. Note that the first 3 decimals are identical.

The spelling of 655983389 in words is "six hundred fifty-five million, nine hundred eighty-three thousand, three hundred eighty-nine".