77128296 has 128 divisors (see below), whose sum is σ = 235852800. Its totient is φ = 20528640.

The previous prime is 77128241. The next prime is 77128297. The reversal of 77128296 is 69282177.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (77128297) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 232851 + ... + 233181.

It is an arithmetic number, because the mean of its divisors is an integer number (1842600).

Almost surely, 2^77128296 is an apocalyptic number.

77128296 is a gapful number since it is divisible by the number (76) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77128296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117926400).

77128296 is an abundant number, since it is smaller than the sum of its proper divisors (158724504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77128296 is a wasteful number, since it uses less digits than its factorization.

77128296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439 (or 435 counting only the distinct ones).

The product of its digits is 84672, while the sum is 42.

The square root of 77128296 is about 8782.2716878949. The cubic root of 77128296 is about 425.6682378055.

The spelling of 77128296 in words is "seventy-seven million, one hundred twenty-eight thousand, two hundred ninety-six".