216257231 has 2 divisors, whose sum is σ = 216257232. Its totient is φ = 216257230.

The previous prime is 216257219. The next prime is 216257287. The reversal of 216257231 is 132752612.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 216257231 - 2¹⁰ = 216256207 is a prime.

It is a super-2 number, since 2×216257231² = 93534379919574722, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 216257194 and 216257203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216257291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108128615 + 108128616.

It is an arithmetic number, because the mean of its divisors is an integer number (108128616).

Almost surely, 2^216257231 is an apocalyptic number.

216257231 is a deficient number, since it is larger than the sum of its proper divisors (1).

216257231 is an equidigital number, since it uses as much as digits as its factorization.

216257231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5040, while the sum is 29.

The square root of 216257231 is about 14705.6870291734. The cubic root of 216257231 is about 600.2380823673.

The spelling of 216257231 in words is "two hundred sixteen million, two hundred fifty-seven thousand, two hundred thirty-one".