77731928 has 8 divisors (see below), whose sum is σ = 145747380. Its totient is φ = 38865960.

The previous prime is 77731903. The next prime is 77731957. The reversal of 77731928 is 82913777.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4858238 + ... + 4858253.

Almost surely, 2^77731928 is an apocalyptic number.

It is an amenable number.

77731928 is a deficient number, since it is larger than the sum of its proper divisors (68015452).

77731928 is a wasteful number, since it uses less digits than its factorization.

77731928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9716497 (or 9716493 counting only the distinct ones).

The product of its digits is 148176, while the sum is 44.

The square root of 77731928 is about 8816.5712156144. The cubic root of 77731928 is about 426.7758276465.

The spelling of 77731928 in words is "seventy-seven million, seven hundred thirty-one thousand, nine hundred twenty-eight".