82780140 has 48 divisors (see below), whose sum is σ = 245421792. Its totient is φ = 20775936.

The previous prime is 82780129. The next prime is 82780141. The reversal of 82780140 is 4108728.

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 = 82780098 and 82780107.

It is not an unprimeable number, because it can be changed into a prime (82780141) 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, 39559 + ... + 41598.

It is an arithmetic number, because the mean of its divisors is an integer number (5112954).

Almost surely, 2^82780140 is an apocalyptic number.

It is an amenable number.

82780140 is an abundant number, since it is smaller than the sum of its proper divisors (162641652).

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

82780140 is a wasteful number, since it uses less digits than its factorization.

82780140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81186 (or 81184 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 82780140 is about 9098.3591927336. The cubic root of 82780140 is about 435.8215679825.

Adding to 82780140 its reverse (4108728), we get a palindrome (86888868).

The spelling of 82780140 in words is "eighty-two million, seven hundred eighty thousand, one hundred forty".