66670777787 has 8 divisors (see below), whose sum is σ = 69788977056. Its totient is φ = 63570867712.

The previous prime is 66670777777. The next prime is 66670777793. The reversal of 66670777787 is 78777707666.

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 66670777787 - 2¹⁰ = 66670776763 is a prime.

It is a super-2 number, since 2×66670777787² (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 (66670777777) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4564838 + ... + 4579419.

It is an arithmetic number, because the mean of its divisors is an integer number (8723622132).

Almost surely, 2^66670777787 is an apocalyptic number.

66670777787 is a deficient number, since it is larger than the sum of its proper divisors (3118199269).

66670777787 is a wasteful number, since it uses less digits than its factorization.

66670777787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9144597.

The product of its (nonzero) digits is 203297472, while the sum is 68.

The spelling of 66670777787 in words is "sixty-six billion, six hundred seventy million, seven hundred seventy-seven thousand, seven hundred eighty-seven".