66212750749 has 2 divisors, whose sum is σ = 66212750750. Its totient is φ = 66212750748.

The previous prime is 66212750717. The next prime is 66212750753. The reversal of 66212750749 is 94705721266.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61779588025 + 4433162724 = 248555^2 + 66582^2 .

It is a cyclic number.

It is not a de Polignac number, because 66212750749 - 2⁵ = 66212750717 is a prime.

It is a super-2 number, since 2×66212750749² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66212750789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33106375374 + 33106375375.

It is an arithmetic number, because the mean of its divisors is an integer number (33106375375).

Almost surely, 2^66212750749 is an apocalyptic number.

It is an amenable number.

66212750749 is a deficient number, since it is larger than the sum of its proper divisors (1).

66212750749 is an equidigital number, since it uses as much as digits as its factorization.

66212750749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1270080, while the sum is 49.

The spelling of 66212750749 in words is "sixty-six billion, two hundred twelve million, seven hundred fifty thousand, seven hundred forty-nine".