81528211 has 2 divisors, whose sum is σ = 81528212. Its totient is φ = 81528210.

The previous prime is 81528203. The next prime is 81528217. The reversal of 81528211 is 11282518.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81528211 - 2³ = 81528203 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81528211.

It is not a weakly prime, because it can be changed into another prime (81528217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40764105 + 40764106.

It is an arithmetic number, because the mean of its divisors is an integer number (40764106).

Almost surely, 2^81528211 is an apocalyptic number.

81528211 is a deficient number, since it is larger than the sum of its proper divisors (1).

81528211 is an equidigital number, since it uses as much as digits as its factorization.

81528211 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1280, while the sum is 28.

The square root of 81528211 is about 9029.2973702277. The cubic root of 81528211 is about 433.6133428258.

The spelling of 81528211 in words is "eighty-one million, five hundred twenty-eight thousand, two hundred eleven".