77284240 has 80 divisors (see below), whose sum is σ = 202415616. Its totient is φ = 27187200.

The previous prime is 77284223. The next prime is 77284247. The reversal of 77284240 is 4248277.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 77284196 and 77284205.

It is not an unprimeable number, because it can be changed into a prime (77284247) 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 15 ways as a sum of consecutive naturals, for example, 25864 + ... + 28696.

Almost surely, 2^77284240 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 77284240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101207808).

77284240 is an abundant number, since it is smaller than the sum of its proper divisors (125131376).

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

77284240 is a wasteful number, since it uses less digits than its factorization.

77284240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2888 (or 2882 counting only the distinct ones).

The product of its (nonzero) digits is 25088, while the sum is 34.

The square root of 77284240 is about 8791.1455453769. The cubic root of 77284240 is about 425.9549277477.

The spelling of 77284240 in words is "seventy-seven million, two hundred eighty-four thousand, two hundred forty".