16397 has 4 divisors (see below), whose sum is σ = 17280. Its totient is φ = 15516.

The previous prime is 16381. The next prime is 16411. The reversal of 16397 is 79361.

It is a happy number.

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: 79361 = 61 ⋅1301.

It is a cyclic number.

It is not a de Polignac number, because 16397 - 2⁴ = 16381 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a nialpdrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16097) 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, 413 + ... + 450.

It is an arithmetic number, because the mean of its divisors is an integer number (4320).

2¹⁶³⁹⁷ is an apocalyptic number.

It is an amenable number.

16397 is a deficient number, since it is larger than the sum of its proper divisors (883).

16397 is an equidigital number, since it uses as much as digits as its factorization.

16397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 882.

The product of its digits is 1134, while the sum is 26.

The square root of 16397 is about 128.0507711808. The cubic root of 16397 is about 25.4051325731.

The spelling of 16397 in words is "sixteen thousand, three hundred ninety-seven".