77788042 has 4 divisors (see below), whose sum is σ = 116682066. Its totient is φ = 38894020.

The previous prime is 77788027. The next prime is 77788043. The reversal of 77788042 is 24088777.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24088777 = 571 ⋅42187.

It can be written as a sum of positive squares in only one way, i.e., 69372241 + 8415801 = 8329^2 + 2901^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 77788042.

It is not an unprimeable number, because it can be changed into a prime (77788043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19447009 + ... + 19447012.

Almost surely, 2^77788042 is an apocalyptic number.

77788042 is a deficient number, since it is larger than the sum of its proper divisors (38894024).

77788042 is a wasteful number, since it uses less digits than its factorization.

77788042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38894023.

The product of its (nonzero) digits is 175616, while the sum is 43.

The square root of 77788042 is about 8819.7529443857. The cubic root of 77788042 is about 426.8784981924.

The spelling of 77788042 in words is "seventy-seven million, seven hundred eighty-eight thousand, forty-two".