82135621 has 2 divisors, whose sum is σ = 82135622. Its totient is φ = 82135620.

The previous prime is 82135607. The next prime is 82135631. The reversal of 82135621 is 12653128.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57988225 + 24147396 = 7615^2 + 4914^2 .

It is a cyclic number.

It is not a de Polignac number, because 82135621 - 2¹³ = 82127429 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 82135621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82135631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41067810 + 41067811.

It is an arithmetic number, because the mean of its divisors is an integer number (41067811).

Almost surely, 2^82135621 is an apocalyptic number.

It is an amenable number.

82135621 is a deficient number, since it is larger than the sum of its proper divisors (1).

82135621 is an equidigital number, since it uses as much as digits as its factorization.

82135621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2880, while the sum is 28.

The square root of 82135621 is about 9062.8704613936. The cubic root of 82135621 is about 434.6875300367.

Adding to 82135621 its reverse (12653128), we get a palindrome (94788749).

The spelling of 82135621 in words is "eighty-two million, one hundred thirty-five thousand, six hundred twenty-one".