66617783 has 2 divisors, whose sum is σ = 66617784. Its totient is φ = 66617782.

The previous prime is 66617779. The next prime is 66617827. The reversal of 66617783 is 38771666.

It is a happy number.

It is an a-pointer prime, because the next prime (66617827) can be obtained adding 66617783 to its sum of digits (44).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66617783 - 2² = 66617779 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66617773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33308891 + 33308892.

It is an arithmetic number, because the mean of its divisors is an integer number (33308892).

Almost surely, 2^66617783 is an apocalyptic number.

66617783 is a deficient number, since it is larger than the sum of its proper divisors (1).

66617783 is an equidigital number, since it uses as much as digits as its factorization.

66617783 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 254016, while the sum is 44.

The square root of 66617783 is about 8161.9717593238. The cubic root of 66617783 is about 405.3810020265.

The spelling of 66617783 in words is "sixty-six million, six hundred seventeen thousand, seven hundred eighty-three".