216377 has 4 divisors (see below), whose sum is σ = 247296. Its totient is φ = 185460.

The previous prime is 216373. The next prime is 216379. The reversal of 216377 is 773612.

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 216377 - 2² = 216373 is a prime.

It is a super-2 number, since 2×216377² = 93638012258, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (216371) 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, 15449 + ... + 15462.

It is an arithmetic number, because the mean of its divisors is an integer number (61824).

2²¹⁶³⁷⁷ is an apocalyptic number.

It is an amenable number.

216377 is a deficient number, since it is larger than the sum of its proper divisors (30919).

216377 is an equidigital number, since it uses as much as digits as its factorization.

216377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30918.

The product of its digits is 1764, while the sum is 26.

The square root of 216377 is about 465.1634121467. The cubic root of 216377 is about 60.0348871183.

Adding to 216377 its reverse (773612), we get a palindrome (989989).

The spelling of 216377 in words is "two hundred sixteen thousand, three hundred seventy-seven".