13664397 has 16 divisors (see below), whose sum is σ = 18905600. Its totient is φ = 8769600.

The previous prime is 13664389. The next prime is 13664419. The reversal of 13664397 is 79346631.

It is not a de Polignac number, because 13664397 - 2³ = 13664389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13664317) 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, 32247 + ... + 32667.

It is an arithmetic number, because the mean of its divisors is an integer number (1181600).

Almost surely, 2^13664397 is an apocalyptic number.

It is an amenable number.

13664397 is a deficient number, since it is larger than the sum of its proper divisors (5241203).

13664397 is a wasteful number, since it uses less digits than its factorization.

13664397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 804.

The product of its digits is 81648, while the sum is 39.

The square root of 13664397 is about 3696.5385159633. The cubic root of 13664397 is about 239.0727940119.

The spelling of 13664397 in words is "thirteen million, six hundred sixty-four thousand, three hundred ninety-seven".