82170990 has 128 divisors (see below), whose sum is σ = 242956800. Its totient is φ = 19595520.

The previous prime is 82170989. The next prime is 82171009. The reversal of 82170990 is 9907128.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 216621 + ... + 216999.

It is an arithmetic number, because the mean of its divisors is an integer number (1898100).

Almost surely, 2^82170990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 82170990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121478400).

82170990 is an abundant number, since it is smaller than the sum of its proper divisors (160785810).

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

82170990 is a wasteful number, since it uses less digits than its factorization.

82170990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 479 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 82170990 is about 9064.8215647083. The cubic root of 82170990 is about 434.7499157055.

The spelling of 82170990 in words is "eighty-two million, one hundred seventy thousand, nine hundred ninety".