10639985 has 4 divisors (see below), whose sum is σ = 12767988. Its totient is φ = 8511984.

The previous prime is 10639949. The next prime is 10639987. The reversal of 10639985 is 58993601.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58993601 = 47 ⋅1255183.

It can be written as a sum of positive squares in 2 ways, for example, as 1079521 + 9560464 = 1039^2 + 3092^2 .

It is a cyclic number.

It is not a de Polignac number, because 10639985 - 2⁶ = 10639921 is a prime.

It is a super-2 number, since 2×10639985² = 226418561600450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10639987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1063994 + ... + 1064003.

It is an arithmetic number, because the mean of its divisors is an integer number (3191997).

Almost surely, 2^10639985 is an apocalyptic number.

It is an amenable number.

10639985 is a deficient number, since it is larger than the sum of its proper divisors (2128003).

10639985 is an equidigital number, since it uses as much as digits as its factorization.

10639985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2128002.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 10639985 is about 3261.8989867867. The cubic root of 10639985 is about 219.9447864196.

The spelling of 10639985 in words is "ten million, six hundred thirty-nine thousand, nine hundred eighty-five".