13887531 has 30 divisors (see below), whose sum is σ = 24139500. Its totient is φ = 7933464.

The previous prime is 13887493. The next prime is 13887539. The reversal of 13887531 is 13578831.

It is not a de Polignac number, because 13887531 - 2⁷ = 13887403 is a prime.

It is a super-2 number, since 2×13887531² = 385727034551922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13887539) 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 29 ways as a sum of consecutive naturals, for example, 2220 + ... + 5718.

It is an arithmetic number, because the mean of its divisors is an integer number (804650).

Almost surely, 2^13887531 is an apocalyptic number.

13887531 is a deficient number, since it is larger than the sum of its proper divisors (10251969).

13887531 is an equidigital number, since it uses as much as digits as its factorization.

13887531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3525 (or 3509 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 13887531 is about 3726.5977781349. The cubic root of 13887531 is about 240.3670944706.

The spelling of 13887531 in words is "thirteen million, eight hundred eighty-seven thousand, five hundred thirty-one".