77312144 has 80 divisors (see below), whose sum is σ = 190821120. Its totient is φ = 29514240.

The previous prime is 77312119. The next prime is 77312153. The reversal of 77312144 is 44121377.

It is a Harshad number since it is a multiple of its sum of digits (29).

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 15 ways as a sum of consecutive naturals, for example, 41309 + ... + 43139.

It is an arithmetic number, because the mean of its divisors is an integer number (2385264).

Almost surely, 2^77312144 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 77312144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95410560).

77312144 is an abundant number, since it is smaller than the sum of its proper divisors (113508976).

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

77312144 is a wasteful number, since it uses less digits than its factorization.

77312144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1888 (or 1882 counting only the distinct ones).

The product of its digits is 4704, while the sum is 29.

The square root of 77312144 is about 8792.7324535664. The cubic root of 77312144 is about 426.0061862195.

The spelling of 77312144 in words is "seventy-seven million, three hundred twelve thousand, one hundred forty-four".