13869987 has 4 divisors (see below), whose sum is σ = 18493320. Its totient is φ = 9246656.

The previous prime is 13869983. The next prime is 13869991. The reversal of 13869987 is 78996831.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (13869983) and next prime (13869991).

It is a cyclic number.

It is not a de Polignac number, because 13869987 - 2² = 13869983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13869983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2311662 + ... + 2311667.

It is an arithmetic number, because the mean of its divisors is an integer number (4623330).

Almost surely, 2^13869987 is an apocalyptic number.

13869987 is a deficient number, since it is larger than the sum of its proper divisors (4623333).

13869987 is an equidigital number, since it uses as much as digits as its factorization.

13869987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4623332.

The product of its digits is 653184, while the sum is 51.

The square root of 13869987 is about 3724.2431445866. The cubic root of 13869987 is about 240.2658339149.

It can be divided in two parts, 138 and 69987, that added together give a triangular number (70125 = T₃₇₄).

The spelling of 13869987 in words is "thirteen million, eight hundred sixty-nine thousand, nine hundred eighty-seven".