77144320 has 72 divisors (see below), whose sum is σ = 201620160. Its totient is φ = 28047360.

The previous prime is 77144311. The next prime is 77144357. The reversal of 77144320 is 2344177.

It is a super-2 number, since 2×77144320² = 11902492216524800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11341 + ... + 16819.

It is an arithmetic number, because the mean of its divisors is an integer number (2800280).

Almost surely, 2^77144320 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77144320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100810080).

77144320 is an abundant number, since it is smaller than the sum of its proper divisors (124475840).

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

77144320 is a wasteful number, since it uses less digits than its factorization.

77144320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5511 (or 5497 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 28.

The square root of 77144320 is about 8783.1839329482. The cubic root of 77144320 is about 425.6977143871.

Adding to 77144320 its reverse (2344177), we get a palindrome (79488497).

The spelling of 77144320 in words is "seventy-seven million, one hundred forty-four thousand, three hundred twenty".