82280640 has 224 divisors, whose sum is σ = 296997120. Its totient is φ = 19132416.

The previous prime is 82280593. The next prime is 82280647. The reversal of 82280640 is 4608228.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 82280598 and 82280607.

It is not an unprimeable number, because it can be changed into a prime (82280647) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 236947 + ... + 237293.

It is an arithmetic number, because the mean of its divisors is an integer number (1325880).

Almost surely, 2^82280640 is an apocalyptic number.

82280640 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 82280640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148498560).

82280640 is an abundant number, since it is smaller than the sum of its proper divisors (214716480).

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

82280640 is a wasteful number, since it uses less digits than its factorization.

82280640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 82280640 is about 9070.8676541993. The cubic root of 82280640 is about 434.9432083343.

Adding to 82280640 its reverse (4608228), we get a palindrome (86888868).

The spelling of 82280640 in words is "eighty-two million, two hundred eighty thousand, six hundred forty".