77728205 has 8 divisors (see below), whose sum is σ = 93686112. Its totient is φ = 61907728.

The previous prime is 77728187. The next prime is 77728237. The reversal of 77728205 is 50282777.

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 77728205 - 2⁶ = 77728141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33107 + ... + 35376.

It is an arithmetic number, because the mean of its divisors is an integer number (11710764).

Almost surely, 2^77728205 is an apocalyptic number.

It is an amenable number.

77728205 is a deficient number, since it is larger than the sum of its proper divisors (15957907).

77728205 is a wasteful number, since it uses less digits than its factorization.

77728205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68715.

The product of its (nonzero) digits is 54880, while the sum is 38.

The square root of 77728205 is about 8816.3600765849. The cubic root of 77728205 is about 426.7690140080.

It can be divided in two parts, 777 and 28205, that added together give a palindrome (28982).

The spelling of 77728205 in words is "seventy-seven million, seven hundred twenty-eight thousand, two hundred five".