216423231 has 4 divisors (see below), whose sum is σ = 288564312. Its totient is φ = 144282152.

The previous prime is 216423227. The next prime is 216423271. The reversal of 216423231 is 132324612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 216423231 - 2² = 216423227 is a prime.

It is a super-2 number, since 2×216423231² = 93678029832958722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216423271) 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, 36070536 + ... + 36070541.

It is an arithmetic number, because the mean of its divisors is an integer number (72141078).

Almost surely, 2^216423231 is an apocalyptic number.

216423231 is a deficient number, since it is larger than the sum of its proper divisors (72141081).

216423231 is an equidigital number, since it uses as much as digits as its factorization.

216423231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72141080.

The product of its digits is 1728, while the sum is 24.

The square root of 216423231 is about 14711.3300214495. The cubic root of 216423231 is about 600.3916248832.

Adding to 216423231 its reverse (132324612), we get a palindrome (348747843).

The spelling of 216423231 in words is "two hundred sixteen million, four hundred twenty-three thousand, two hundred thirty-one".