82505181 has 24 divisors (see below), whose sum is σ = 121730112. Its totient is φ = 49667200.

The previous prime is 82505179. The next prime is 82505197. The reversal of 82505181 is 18150528.

It is not a de Polignac number, because 82505181 - 2¹ = 82505179 is a prime.

It is a super-2 number, since 2×82505181² = 13614209783685522, which contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82505081) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 59941 + ... + 61301.

It is an arithmetic number, because the mean of its divisors is an integer number (5072088).

Almost surely, 2^82505181 is an apocalyptic number.

It is an amenable number.

82505181 is a deficient number, since it is larger than the sum of its proper divisors (39224931).

82505181 is a wasteful number, since it uses less digits than its factorization.

82505181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1553 (or 1542 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 30.

The square root of 82505181 is about 9083.2362624783. The cubic root of 82505181 is about 435.3384972630.

It can be divided in two parts, 8250 and 5181, that added together give a palindrome (13431).

The spelling of 82505181 in words is "eighty-two million, five hundred five thousand, one hundred eighty-one".