82521180225 has 81 divisors (see below), whose sum is σ = 162556279977. Its totient is φ = 39987288000.

The previous prime is 82521180191. The next prime is 82521180229. The reversal of 82521180225 is 52208112528.

The square root of 82521180225 is 287265.

It is a perfect power (a square), and thus also a powerful number.

82521180225 is a `hidden beast` number, since 8 + 252 + 1 + 180 + 225 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 50103897921 + 32417282304 = 223839^2 + 180048^2 .

It is not a de Polignac number, because 82521180225 - 2¹⁷ = 82521049153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 82521180225.

It is not an unprimeable number, because it can be changed into a prime (82521180229) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 47397855 + ... + 47399595.

Almost surely, 2^82521180225 is an apocalyptic number.

82521180225 is the 287265-th square number.

82521180225 is the 143633-rd centered octagonal number.

It is an amenable number.

82521180225 is a deficient number, since it is larger than the sum of its proper divisors (80035099752).

82521180225 is a wasteful number, since it uses less digits than its factorization.

82521180225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3520 (or 1760 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 36.

Multiplying 82521180225 by its sum of digits (36), we get a square (2970762488100 = 1723590²).

The spelling of 82521180225 in words is "eighty-two billion, five hundred twenty-one million, one hundred eighty thousand, two hundred twenty-five".