77438040 has 128 divisors (see below), whose sum is σ = 242300160. Its totient is φ = 19782144.

The previous prime is 77438029. The next prime is 77438047. The reversal of 77438040 is 4083477.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 77437992 and 77438010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77438047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 474999 + ... + 475161.

It is an arithmetic number, because the mean of its divisors is an integer number (1892970).

Almost surely, 2^77438040 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 77438040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121150080).

77438040 is an abundant number, since it is smaller than the sum of its proper divisors (164862120).

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

77438040 is a wasteful number, since it uses less digits than its factorization.

77438040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 33.

The square root of 77438040 is about 8799.8886356590. Note that the first 3 decimals coincide. The cubic root of 77438040 is about 426.2372986357.

The spelling of 77438040 in words is "seventy-seven million, four hundred thirty-eight thousand, forty".