82811640 has 64 divisors (see below), whose sum is σ = 249933600. Its totient is φ = 21949952.

The previous prime is 82811639. The next prime is 82811647. The reversal of 82811640 is 4611828.

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 = 82811598 and 82811607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82811647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18766 + ... + 22754.

Almost surely, 2^82811640 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 82811640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124966800).

82811640 is an abundant number, since it is smaller than the sum of its proper divisors (167121960).

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

82811640 is a wasteful number, since it uses less digits than its factorization.

82811640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4176 (or 4172 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 82811640 is about 9100.0901094440. The cubic root of 82811640 is about 435.8768414592.

The spelling of 82811640 in words is "eighty-two million, eight hundred eleven thousand, six hundred forty".