66807079 has 4 divisors (see below), whose sum is σ = 68360776. Its totient is φ = 65253384.

The previous prime is 66807071. The next prime is 66807119. The reversal of 66807079 is 97070866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66807079 - 2³ = 66807071 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 1553653 = 66807079 / (6 + 6 + 8 + 0 + 7 + 0 + 7 + 9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66807071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 776784 + ... + 776869.

It is an arithmetic number, because the mean of its divisors is an integer number (17090194).

Almost surely, 2^66807079 is an apocalyptic number.

66807079 is a deficient number, since it is larger than the sum of its proper divisors (1553697).

66807079 is a wasteful number, since it uses less digits than its factorization.

66807079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1553696.

The product of its (nonzero) digits is 127008, while the sum is 43.

The square root of 66807079 is about 8173.5597508063. The cubic root of 66807079 is about 405.7646054724.

The spelling of 66807079 in words is "sixty-six million, eight hundred seven thousand, seventy-nine".