77243320 has 128 divisors (see below), whose sum is σ = 223948800. Its totient is φ = 23270400.

The previous prime is 77243317. The next prime is 77243321. The reversal of 77243320 is 2334277.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77243321) 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, 95076 + ... + 95884.

It is an arithmetic number, because the mean of its divisors is an integer number (1749600).

Almost surely, 2^77243320 is an apocalyptic number.

77243320 is a gapful number since it is divisible by the number (70) 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 77243320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111974400).

77243320 is an abundant number, since it is smaller than the sum of its proper divisors (146705480).

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

77243320 is a wasteful number, since it uses less digits than its factorization.

77243320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 869 (or 865 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 28.

The square root of 77243320 is about 8788.8178954851. The cubic root of 77243320 is about 425.8797371146.

Adding to 77243320 its reverse (2334277), we get a palindrome (79577597).

The spelling of 77243320 in words is "seventy-seven million, two hundred forty-three thousand, three hundred twenty".