85535581 has 2 divisors, whose sum is σ = 85535582. Its totient is φ = 85535580.

The previous prime is 85535561. The next prime is 85535623. The reversal of 85535581 is 18553558.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83083225 + 2452356 = 9115^2 + 1566^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85535581 is a prime.

It is a super-2 number, since 2×85535581² = 14632671234015122, which contains 22 as substring.

It is equal to p_4973098 and since 85535581 and 4973098 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85535501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42767790 + 42767791.

It is an arithmetic number, because the mean of its divisors is an integer number (42767791).

Almost surely, 2^85535581 is an apocalyptic number.

It is an amenable number.

85535581 is a deficient number, since it is larger than the sum of its proper divisors (1).

85535581 is an equidigital number, since it uses as much as digits as its factorization.

85535581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120000, while the sum is 40.

The square root of 85535581 is about 9248.5448044544. The cubic root of 85535581 is about 440.6045082837.

The spelling of 85535581 in words is "eighty-five million, five hundred thirty-five thousand, five hundred eighty-one".