39720085 has 4 divisors (see below), whose sum is σ = 47664108. Its totient is φ = 31776064.

The previous prime is 39720073. The next prime is 39720113. The reversal of 39720085 is 58002793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58002793 = 17 ⋅3411929.

It can be written as a sum of positive squares in 2 ways, for example, as 30393169 + 9326916 = 5513^2 + 3054^2 .

It is a cyclic number.

It is not a de Polignac number, because 39720085 - 2¹⁷ = 39589013 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 39720085.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3972004 + ... + 3972013.

It is an arithmetic number, because the mean of its divisors is an integer number (11916027).

Almost surely, 2^39720085 is an apocalyptic number.

It is an amenable number.

39720085 is a deficient number, since it is larger than the sum of its proper divisors (7944023).

39720085 is an equidigital number, since it uses as much as digits as its factorization.

39720085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7944022.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 39720085 is about 6302.3872461156. The cubic root of 39720085 is about 341.1955746950.

The spelling of 39720085 in words is "thirty-nine million, seven hundred twenty thousand, eighty-five".