77828509 has 8 divisors (see below), whose sum is σ = 85979520. Its totient is φ = 69856800.

The previous prime is 77828461. The next prime is 77828549. The reversal of 77828509 is 90582877.

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 77828509 - 2¹³ = 77820317 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77828549) 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 in 7 ways as a sum of consecutive naturals, for example, 43912 + ... + 45649.

It is an arithmetic number, because the mean of its divisors is an integer number (10747440).

Almost surely, 2^77828509 is an apocalyptic number.

77828509 is a gapful number since it is divisible by the number (79) formed by its first and last digit.

It is an amenable number.

77828509 is a deficient number, since it is larger than the sum of its proper divisors (8151011).

77828509 is a wasteful number, since it uses less digits than its factorization.

77828509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89651.

The product of its (nonzero) digits is 282240, while the sum is 46.

The square root of 77828509 is about 8822.0467579808. The cubic root of 77828509 is about 426.9525091290.

The spelling of 77828509 in words is "seventy-seven million, eight hundred twenty-eight thousand, five hundred nine".