66641072669 has 2 divisors, whose sum is σ = 66641072670. Its totient is φ = 66641072668.

The previous prime is 66641072623. The next prime is 66641072671. The reversal of 66641072669 is 96627014666.

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., 62206844569 + 4434228100 = 249413^2 + 66590^2 .

It is a cyclic number.

It is not a de Polignac number, because 66641072669 - 2²⁰ = 66640024093 is a prime.

It is a super-2 number, since 2×66641072669² (a number of 22 digits) contains 22 as substring.

Together with 66641072671, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66641072669.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66641072699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33320536334 + 33320536335.

It is an arithmetic number, because the mean of its divisors is an integer number (33320536335).

Almost surely, 2^66641072669 is an apocalyptic number.

It is an amenable number.

66641072669 is a deficient number, since it is larger than the sum of its proper divisors (1).

66641072669 is an equidigital number, since it uses as much as digits as its factorization.

66641072669 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3919104, while the sum is 53.

The spelling of 66641072669 in words is "sixty-six billion, six hundred forty-one million, seventy-two thousand, six hundred sixty-nine".