85821137 has 2 divisors, whose sum is σ = 85821138. Its totient is φ = 85821136.

The previous prime is 85821091. The next prime is 85821149. The reversal of 85821137 is 73112858.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63504961 + 22316176 = 7969^2 + 4724^2 .

It is a cyclic number.

It is not a de Polignac number, because 85821137 - 2¹² = 85817041 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 85821097 and 85821106.

It is not a weakly prime, because it can be changed into another prime (85826137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42910568 + 42910569.

It is an arithmetic number, because the mean of its divisors is an integer number (42910569).

Almost surely, 2^85821137 is an apocalyptic number.

It is an amenable number.

85821137 is a deficient number, since it is larger than the sum of its proper divisors (1).

85821137 is an equidigital number, since it uses as much as digits as its factorization.

85821137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13440, while the sum is 35.

The square root of 85821137 is about 9263.9698293982. The cubic root of 85821137 is about 441.0942752601.

It can be divided in two parts, 85821 and 137, that added together give a palindrome (85958).

The spelling of 85821137 in words is "eighty-five million, eight hundred twenty-one thousand, one hundred thirty-seven".