66777707 has 4 divisors (see below), whose sum is σ = 66892056. Its totient is φ = 66663360.

The previous prime is 66777703. The next prime is 66777713. The reversal of 66777707 is 70777766.

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 66777707 - 2² = 66777703 is a prime.

It is a super-3 number, since 3×66777707³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66777703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56294 + ... + 57467.

It is an arithmetic number, because the mean of its divisors is an integer number (16723014).

Almost surely, 2^66777707 is an apocalyptic number.

66777707 is a deficient number, since it is larger than the sum of its proper divisors (114349).

66777707 is a wasteful number, since it uses less digits than its factorization.

66777707 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114348.

The product of its (nonzero) digits is 605052, while the sum is 47.

The square root of 66777707 is about 8171.7627841244. The cubic root of 66777707 is about 405.7051314106.

The spelling of 66777707 in words is "sixty-six million, seven hundred seventy-seven thousand, seven hundred seven".