77825280 has 144 divisors (see below), whose sum is σ = 267845760. Its totient is φ = 19144704.

The previous prime is 77825263. The next prime is 77825281. The reversal of 77825280 is 8252877.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77825281) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49141 + ... + 50699.

It is an arithmetic number, because the mean of its divisors is an integer number (1860040).

Almost surely, 2^77825280 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 77825280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133922880).

77825280 is an abundant number, since it is smaller than the sum of its proper divisors (190020480).

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

77825280 is a wasteful number, since it uses less digits than its factorization.

77825280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1596 (or 1582 counting only the distinct ones).

The product of its (nonzero) digits is 62720, while the sum is 39.

The square root of 77825280 is about 8821.8637486645. The cubic root of 77825280 is about 426.9466044859.

It can be divided in two parts, 7 and 7825280, that added together give a palindrome (7825287).

The spelling of 77825280 in words is "seventy-seven million, eight hundred twenty-five thousand, two hundred eighty".