85720237 has 2 divisors, whose sum is σ = 85720238. Its totient is φ = 85720236.

The previous prime is 85720213. The next prime is 85720291. The reversal of 85720237 is 73202758.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 82555396 + 3164841 = 9086^2 + 1779^2 .

It is a cyclic number.

It is not a de Polignac number, because 85720237 - 2⁷ = 85720109 is a prime.

It is a nialpdrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85720207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42860118 + 42860119.

It is an arithmetic number, because the mean of its divisors is an integer number (42860119).

Almost surely, 2^85720237 is an apocalyptic number.

It is an amenable number.

85720237 is a deficient number, since it is larger than the sum of its proper divisors (1).

85720237 is an equidigital number, since it uses as much as digits as its factorization.

85720237 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 85720237 is about 9258.5223983096. The cubic root of 85720237 is about 440.9213424706.

The spelling of 85720237 in words is "eighty-five million, seven hundred twenty thousand, two hundred thirty-seven".