13721545 has 4 divisors (see below), whose sum is σ = 16465860. Its totient is φ = 10977232.

The previous prime is 13721537. The next prime is 13721563. The reversal of 13721545 is 54512731.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8573184 + 5148361 = 2928^2 + 2269^2 .

It is a cyclic number.

It is not a de Polignac number, because 13721545 - 2³ = 13721537 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1372150 + ... + 1372159.

It is an arithmetic number, because the mean of its divisors is an integer number (4116465).

Almost surely, 2^13721545 is an apocalyptic number.

It is an amenable number.

13721545 is a deficient number, since it is larger than the sum of its proper divisors (2744315).

13721545 is an equidigital number, since it uses as much as digits as its factorization.

13721545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2744314.

The product of its digits is 4200, while the sum is 28.

The square root of 13721545 is about 3704.2603850162. The cubic root of 13721545 is about 239.4056182955.

The spelling of 13721545 in words is "thirteen million, seven hundred twenty-one thousand, five hundred forty-five".