13219681 has 4 divisors (see below), whose sum is σ = 13230000. Its totient is φ = 13209364.

The previous prime is 13219667. The next prime is 13219691. The reversal of 13219681 is 18691231.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 13219681 - 2¹⁹ = 12695393 is a prime.

It is a super-2 number, since 2×13219681² = 349519931483522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13219601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2911 + ... + 5908.

It is an arithmetic number, because the mean of its divisors is an integer number (3307500).

Almost surely, 2^13219681 is an apocalyptic number.

It is an amenable number.

13219681 is a deficient number, since it is larger than the sum of its proper divisors (10319).

13219681 is an equidigital number, since it uses as much as digits as its factorization.

13219681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10318.

The product of its digits is 2592, while the sum is 31.

The square root of 13219681 is about 3635.8879245653. The cubic root of 13219681 is about 236.4505481486.

The spelling of 13219681 in words is "thirteen million, two hundred nineteen thousand, six hundred eighty-one".