13504721 has 8 divisors (see below), whose sum is σ = 13769184. Its totient is φ = 13242240.

The previous prime is 13504717. The next prime is 13504727. The reversal of 13504721 is 12740531.

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

It is a cyclic number.

It is not a de Polignac number, because 13504721 - 2² = 13504717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13504727) 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, 23366 + ... + 23936.

It is an arithmetic number, because the mean of its divisors is an integer number (1721148).

Almost surely, 2^13504721 is an apocalyptic number.

It is an amenable number.

13504721 is a deficient number, since it is larger than the sum of its proper divisors (264463).

13504721 is an equidigital number, since it uses as much as digits as its factorization.

13504721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 991.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 13504721 is about 3674.8770047445. The cubic root of 13504721 is about 238.1379105618.

The spelling of 13504721 in words is "thirteen million, five hundred four thousand, seven hundred twenty-one".