1661773133 has 2 divisors, whose sum is σ = 1661773134. Its totient is φ = 1661773132.

The previous prime is 1661773111. The next prime is 1661773159. The reversal of 1661773133 is 3313771661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1456338244 + 205434889 = 38162^2 + 14333^2 .

It is an emirp because it is prime and its reverse (3313771661) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1661773133 is a prime.

It is a super-2 number, since 2×1661773133² = 5522979891121271378, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661773733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830886566 + 830886567.

It is an arithmetic number, because the mean of its divisors is an integer number (830886567).

Almost surely, 2^1661773133 is an apocalyptic number.

It is an amenable number.

1661773133 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661773133 is an equidigital number, since it uses as much as digits as its factorization.

1661773133 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47628, while the sum is 38.

The square root of 1661773133 is about 40764.8516862260. The cubic root of 1661773133 is about 1184.4695788215.

The spelling of 1661773133 in words is "one billion, six hundred sixty-one million, seven hundred seventy-three thousand, one hundred thirty-three".