13509987 has 8 divisors (see below), whose sum is σ = 18081360. Its totient is φ = 8972640.

The previous prime is 13509983. The next prime is 13509989. The reversal of 13509987 is 78990531.

It is a happy number.

13509987 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 13509987 - 2² = 13509983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13509983) 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, 7564 + ... + 9177.

It is an arithmetic number, because the mean of its divisors is an integer number (2260170).

Almost surely, 2^13509987 is an apocalyptic number.

13509987 is a deficient number, since it is larger than the sum of its proper divisors (4571373).

13509987 is a wasteful number, since it uses less digits than its factorization.

13509987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17013.

The product of its (nonzero) digits is 68040, while the sum is 42.

The square root of 13509987 is about 3675.5934214763. The cubic root of 13509987 is about 238.1688595233.

The spelling of 13509987 in words is "thirteen million, five hundred nine thousand, nine hundred eighty-seven".