666638333 has 2 divisors, whose sum is σ = 666638334. Its totient is φ = 666638332.

The previous prime is 666638327. The next prime is 666638339. The reversal of 666638333 is 333836666.

It is a balanced prime because it is at equal distance from previous prime (666638327) and next prime (666638339).

It can be written as a sum of positive squares in only one way, i.e., 645312409 + 21325924 = 25403^2 + 4618^2 .

It is a cyclic number.

It is not a de Polignac number, because 666638333 - 2¹² = 666634237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666638339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333319166 + 333319167.

It is an arithmetic number, because the mean of its divisors is an integer number (333319167).

Almost surely, 2^666638333 is an apocalyptic number.

It is an amenable number.

666638333 is a deficient number, since it is larger than the sum of its proper divisors (1).

666638333 is an equidigital number, since it uses as much as digits as its factorization.

666638333 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 44.

The square root of 666638333 is about 25819.3402897905. The cubic root of 666638333 is about 873.5680886921.

The spelling of 666638333 in words is "six hundred sixty-six million, six hundred thirty-eight thousand, three hundred thirty-three".