661363133 has 2 divisors, whose sum is σ = 661363134. Its totient is φ = 661363132.

The previous prime is 661363127. The next prime is 661363141. The reversal of 661363133 is 331363166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 637966564 + 23396569 = 25258^2 + 4837^2 .

It is a cyclic number.

It is not a de Polignac number, because 661363133 - 2⁶ = 661363069 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 661363133.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661363033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330681566 + 330681567.

It is an arithmetic number, because the mean of its divisors is an integer number (330681567).

Almost surely, 2^661363133 is an apocalyptic number.

It is an amenable number.

661363133 is a deficient number, since it is larger than the sum of its proper divisors (1).

661363133 is an equidigital number, since it uses as much as digits as its factorization.

661363133 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17496, while the sum is 32.

The square root of 661363133 is about 25716.9814130663. The cubic root of 661363133 is about 871.2577628377.

The spelling of 661363133 in words is "six hundred sixty-one million, three hundred sixty-three thousand, one hundred thirty-three".