82180720 has 40 divisors (see below), whose sum is σ = 202312944. Its totient is φ = 30938112.

The previous prime is 82180711. The next prime is 82180727. The reversal of 82180720 is 2708128.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82180727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28854 + ... + 31573.

Almost surely, 2^82180720 is an apocalyptic number.

82180720 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

82180720 is an abundant number, since it is smaller than the sum of its proper divisors (120132224).

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

82180720 is a wasteful number, since it uses less digits than its factorization.

82180720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60457 (or 60451 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 82180720 is about 9065.3582389225. The cubic root of 82180720 is about 434.7670748421.

Adding to 82180720 its reverse (2708128), we get a palindrome (84888848).

The spelling of 82180720 in words is "eighty-two million, one hundred eighty thousand, seven hundred twenty".