80778720 has 96 divisors (see below), whose sum is σ = 277603200. Its totient is φ = 19581440.

The previous prime is 80778707. The next prime is 80778721. The reversal of 80778720 is 2787708.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80778721) 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, 2370 + ... + 12929.

It is an arithmetic number, because the mean of its divisors is an integer number (2891700).

Almost surely, 2^80778720 is an apocalyptic number.

80778720 is a gapful number since it is divisible by the number (80) 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 80778720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138801600).

80778720 is an abundant number, since it is smaller than the sum of its proper divisors (196824480).

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

80778720 is a wasteful number, since it uses less digits than its factorization.

80778720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15328 (or 15320 counting only the distinct ones).

The product of its (nonzero) digits is 43904, while the sum is 39.

The square root of 80778720 is about 8987.6982592875. The cubic root of 80778720 is about 432.2805105464.

The spelling of 80778720 in words is "eighty million, seven hundred seventy-eight thousand, seven hundred twenty".