82212805 has 8 divisors (see below), whose sum is σ = 100517112. Its totient is φ = 64529088.

The previous prime is 82212803. The next prime is 82212827. The reversal of 82212805 is 50821228.

It can be written as a sum of positive squares in 4 ways, for example, as 30846916 + 51365889 = 5554^2 + 7167^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 82212805 - 2¹ = 82212803 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82212803) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 154854 + ... + 155383.

It is an arithmetic number, because the mean of its divisors is an integer number (12564639).

Almost surely, 2^82212805 is an apocalyptic number.

It is an amenable number.

82212805 is a deficient number, since it is larger than the sum of its proper divisors (18304307).

82212805 is a wasteful number, since it uses less digits than its factorization.

82212805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310295.

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 82212805 is about 9067.1277149933. The cubic root of 82212805 is about 434.8236480732.

It can be divided in two parts, 8221 and 2805, that added together give a triangular number (11026 = T₁₄₈).

The spelling of 82212805 in words is "eighty-two million, two hundred twelve thousand, eight hundred five".