82531220 has 12 divisors (see below), whose sum is σ = 173315604. Its totient is φ = 33012480.

The previous prime is 82531219. The next prime is 82531223. The reversal of 82531220 is 2213528.

It can be written as a sum of positive squares in 2 ways, for example, as 64705936 + 17825284 = 8044^2 + 4222^2 .

It is a super-2 number, since 2×82531220² = 13622804549376800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82531223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2063261 + ... + 2063300.

It is an arithmetic number, because the mean of its divisors is an integer number (14442967).

Almost surely, 2^82531220 is an apocalyptic number.

It is an amenable number.

82531220 is an abundant number, since it is smaller than the sum of its proper divisors (90784384).

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

82531220 is a wasteful number, since it uses less digits than its factorization.

82531220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4126570 (or 4126568 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 82531220 is about 9084.6695041702. The cubic root of 82531220 is about 435.3842906975.

Adding to 82531220 its reverse (2213528), we get a palindrome (84744748).

The spelling of 82531220 in words is "eighty-two million, five hundred thirty-one thousand, two hundred twenty".