1666633333 has 2 divisors, whose sum is σ = 1666633334. Its totient is φ = 1666633332.

The previous prime is 1666633321. The next prime is 1666633349. The reversal of 1666633333 is 3333366661.

It is a happy number.

It is the 16667-th star number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1020355249 + 646278084 = 31943^2 + 25422^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666633333 - 2¹⁷ = 1666502261 is a prime.

It is a super-4 number, since 4×1666633333⁴ (a number of 38 digits) contains 4444 as substring.

1666633333 is a modest number, since divided by 33333 gives 16666 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666633303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833316666 + 833316667.

It is an arithmetic number, because the mean of its divisors is an integer number (833316667).

Almost surely, 2^1666633333 is an apocalyptic number.

It is an amenable number.

1666633333 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666633333 is an equidigital number, since it uses as much as digits as its factorization.

1666633333 is an evil number, because the sum of its binary digits is even.

The product of its digits is 314928, while the sum is 40.

The square root of 1666633333 is about 40824.4207919721. The cubic root of 1666633333 is about 1185.6231971576.

Adding to 1666633333 its reverse (3333366661), we get a palindrome (4999999994).

It can be divided in two parts, 16666 and 33333, that multiplied together give a triangular number (555527778 = T₃₃₃₃₂).

The spelling of 1666633333 in words is "one billion, six hundred sixty-six million, six hundred thirty-three thousand, three hundred thirty-three".