39915985 has 8 divisors (see below), whose sum is σ = 48393576. Its totient is φ = 31603200.

The previous prime is 39915961. The next prime is 39915989. The reversal of 39915985 is 58951993.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5716881 + 34199104 = 2391^2 + 5848^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 39915985 - 2⁷ = 39915857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39915989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40666 + ... + 41635.

It is an arithmetic number, because the mean of its divisors is an integer number (6049197).

Almost surely, 2^39915985 is an apocalyptic number.

It is an amenable number.

39915985 is a deficient number, since it is larger than the sum of its proper divisors (8477591).

39915985 is an equidigital number, since it uses as much as digits as its factorization.

39915985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82403.

The product of its digits is 437400, while the sum is 49.

The square root of 39915985 is about 6317.9098600724. The cubic root of 39915985 is about 341.7555821200.

It can be divided in two parts, 399 and 15985, that added together give a 14-th power (16384 = 2¹⁴).

The spelling of 39915985 in words is "thirty-nine million, nine hundred fifteen thousand, nine hundred eighty-five".