85402609 has 2 divisors, whose sum is σ = 85402610. Its totient is φ = 85402608.

The previous prime is 85402607. The next prime is 85402633. The reversal of 85402609 is 90620458.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62362609 + 23040000 = 7897^2 + 4800^2 .

It is a cyclic number.

It is not a de Polignac number, because 85402609 - 2¹ = 85402607 is a prime.

Together with 85402607, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (85402607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42701304 + 42701305.

It is an arithmetic number, because the mean of its divisors is an integer number (42701305).

Almost surely, 2^85402609 is an apocalyptic number.

It is an amenable number.

85402609 is a deficient number, since it is larger than the sum of its proper divisors (1).

85402609 is an equidigital number, since it uses as much as digits as its factorization.

85402609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 85402609 is about 9241.3532017773. The cubic root of 85402609 is about 440.3760713837.

The spelling of 85402609 in words is "eighty-five million, four hundred two thousand, six hundred nine".