66406672579 has 6 divisors (see below), whose sum is σ = 71907817236. Its totient is φ = 61298466840.

The previous prime is 66406672573. The next prime is 66406672583. The reversal of 66406672579 is 97527660466.

It is a happy number.

It is not a de Polignac number, because 66406672579 - 2⁹ = 66406672067 is a prime.

It is a super-2 number, since 2×66406672579² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66406672573) 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 in 5 ways as a sum of consecutive naturals, for example, 196469277 + ... + 196469614.

It is an arithmetic number, because the mean of its divisors is an integer number (11984636206).

Almost surely, 2^66406672579 is an apocalyptic number.

66406672579 is a deficient number, since it is larger than the sum of its proper divisors (5501144657).

66406672579 is a wasteful number, since it uses less digits than its factorization.

66406672579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392938917 (or 392938904 counting only the distinct ones).

The product of its (nonzero) digits is 22861440, while the sum is 58.

The spelling of 66406672579 in words is "sixty-six billion, four hundred six million, six hundred seventy-two thousand, five hundred seventy-nine".