66397 has 4 divisors (see below), whose sum is σ = 67456. Its totient is φ = 65340.

The previous prime is 66383. The next prime is 66403. The reversal of 66397 is 79366.

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.

It is a cyclic number.

It is not a de Polignac number, because 66397 - 2¹⁵ = 33629 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 (66337) 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, 429 + ... + 562.

It is an arithmetic number, because the mean of its divisors is an integer number (16864).

2⁶⁶³⁹⁷ is an apocalyptic number.

66397 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

It is an amenable number.

66397 is a deficient number, since it is larger than the sum of its proper divisors (1059).

66397 is an equidigital number, since it uses as much as digits as its factorization.

66397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058.

The product of its digits is 6804, while the sum is 31.

The square root of 66397 is about 257.6761533398. The cubic root of 66397 is about 40.4932671834.

Subtracting from 66397 its sum of digits (31), we obtain a palindrome (66366).

The spelling of 66397 in words is "sixty-six thousand, three hundred ninety-seven".