66965954849 has 2 divisors, whose sum is σ = 66965954850. Its totient is φ = 66965954848.

The previous prime is 66965954807. The next prime is 66965954921. The reversal of 66965954849 is 94845956966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39320907025 + 27645047824 = 198295^2 + 166268^2 .

It is a cyclic number.

It is not a de Polignac number, because 66965954849 - 2³² = 62670987553 is a prime.

It is a super-2 number, since 2×66965954849² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66965924849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33482977424 + 33482977425.

It is an arithmetic number, because the mean of its divisors is an integer number (33482977425).

Almost surely, 2^66965954849 is an apocalyptic number.

It is an amenable number.

66965954849 is a deficient number, since it is larger than the sum of its proper divisors (1).

66965954849 is an equidigital number, since it uses as much as digits as its factorization.

66965954849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 503884800, while the sum is 71.

The spelling of 66965954849 in words is "sixty-six billion, nine hundred sixty-five million, nine hundred fifty-four thousand, eight hundred forty-nine".