77938666 has 8 divisors (see below), whose sum is σ = 125900964. Its totient is φ = 35971680.

The previous prime is 77938639. The next prime is 77938667. The reversal of 77938666 is 66683977.

It can be written as a sum of positive squares in 2 ways, for example, as 71048041 + 6890625 = 8429^2 + 2625^2 .

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

It is not an unprimeable number, because it can be changed into a prime (77938667) 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, 1498795 + ... + 1498846.

Almost surely, 2^77938666 is an apocalyptic number.

77938666 is a deficient number, since it is larger than the sum of its proper divisors (47962298).

77938666 is a wasteful number, since it uses less digits than its factorization.

77938666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2997656.

The product of its digits is 2286144, while the sum is 52.

The square root of 77938666 is about 8828.2878294718. The cubic root of 77938666 is about 427.1538476714.

The spelling of 77938666 in words is "seventy-seven million, nine hundred thirty-eight thousand, six hundred sixty-six".