13215649 has 4 divisors (see below), whose sum is σ = 13275136. Its totient is φ = 13156164.

The previous prime is 13215617. The next prime is 13215661. The reversal of 13215649 is 94651231.

13215649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 94651231 = 2699 ⋅35069.

It is a cyclic number.

It is not a de Polignac number, because 13215649 - 2⁵ = 13215617 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13215649.

It is not an unprimeable number, because it can be changed into a prime (13215049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29409 + ... + 29854.

It is an arithmetic number, because the mean of its divisors is an integer number (3318784).

Almost surely, 2^13215649 is an apocalyptic number.

It is an amenable number.

13215649 is a deficient number, since it is larger than the sum of its proper divisors (59487).

13215649 is an equidigital number, since it uses as much as digits as its factorization.

13215649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59486.

The product of its digits is 6480, while the sum is 31.

The square root of 13215649 is about 3635.3334097439. Note that the first 3 decimals coincide. The cubic root of 13215649 is about 236.4265065812.

The spelling of 13215649 in words is "thirteen million, two hundred fifteen thousand, six hundred forty-nine".