85620809 has 2 divisors, whose sum is σ = 85620810. Its totient is φ = 85620808.

The previous prime is 85620797. The next prime is 85620827. The reversal of 85620809 is 90802658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44622400 + 40998409 = 6680^2 + 6403^2 .

It is a cyclic number.

It is not a de Polignac number, because 85620809 - 2¹⁶ = 85555273 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (85620709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42810404 + 42810405.

It is an arithmetic number, because the mean of its divisors is an integer number (42810405).

Almost surely, 2^85620809 is an apocalyptic number.

It is an amenable number.

85620809 is a deficient number, since it is larger than the sum of its proper divisors (1).

85620809 is an equidigital number, since it uses as much as digits as its factorization.

85620809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 85620809 is about 9253.1513010433. The cubic root of 85620809 is about 440.7507997459.

The spelling of 85620809 in words is "eighty-five million, six hundred twenty thousand, eight hundred nine".