66799999 has 8 divisors (see below), whose sum is σ = 76463648. Its totient is φ = 57166560.

The previous prime is 66799979. The next prime is 66800003. The reversal of 66799999 is 99999766.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66799999 - 2⁹ = 66799487 is a prime.

It is a Duffinian number.

66799999 is a modest number, since divided by 9999 gives 6679 as remainder.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 66799999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66799949) 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 7 ways as a sum of consecutive naturals, for example, 2592 + ... + 11845.

It is an arithmetic number, because the mean of its divisors is an integer number (9557956).

Almost surely, 2^66799999 is an apocalyptic number.

66799999 is a deficient number, since it is larger than the sum of its proper divisors (9663649).

66799999 is a wasteful number, since it uses less digits than its factorization.

66799999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15105.

The product of its digits is 14880348, while the sum is 64.

The square root of 66799999 is about 8173.1266355049. The cubic root of 66799999 is about 405.7502710888.

The spelling of 66799999 in words is "sixty-six million, seven hundred ninety-nine thousand, nine hundred ninety-nine".