85081021 has 2 divisors, whose sum is σ = 85081022. Its totient is φ = 85081020.

The previous prime is 85081013. The next prime is 85081037. The reversal of 85081021 is 12018058.

85081021 is nontrivially palindromic in base 3.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73102500 + 11978521 = 8550^2 + 3461^2 .

It is a cyclic number.

It is not a de Polignac number, because 85081021 - 2³ = 85081013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85081001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42540510 + 42540511.

It is an arithmetic number, because the mean of its divisors is an integer number (42540511).

Almost surely, 2^85081021 is an apocalyptic number.

It is an amenable number.

85081021 is a deficient number, since it is larger than the sum of its proper divisors (1).

85081021 is an equidigital number, since it uses as much as digits as its factorization.

85081021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 25.

The square root of 85081021 is about 9223.9373913747. The cubic root of 85081021 is about 439.8226230630.

Adding to 85081021 its reverse (12018058), we get a palindrome (97099079).

The spelling of 85081021 in words is "eighty-five million, eighty-one thousand, twenty-one".