13650721 has 16 divisors (see below), whose sum is σ = 16536960. Its totient is φ = 11007360.

The previous prime is 13650709. The next prime is 13650787. The reversal of 13650721 is 12705631.

It is not a de Polignac number, because 13650721 - 2¹⁵ = 13617953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13650701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25941 + ... + 26461.

It is an arithmetic number, because the mean of its divisors is an integer number (1033560).

Almost surely, 2^13650721 is an apocalyptic number.

It is an amenable number.

13650721 is a deficient number, since it is larger than the sum of its proper divisors (2886239).

13650721 is a wasteful number, since it uses less digits than its factorization.

13650721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 13650721 is about 3694.6882141799. The cubic root of 13650721 is about 238.9930087881.

The spelling of 13650721 in words is "thirteen million, six hundred fifty thousand, seven hundred twenty-one".