216239957 has 2 divisors, whose sum is σ = 216239958. Its totient is φ = 216239956.

The previous prime is 216239953. The next prime is 216239963. The reversal of 216239957 is 759932612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 203034001 + 13205956 = 14249^2 + 3634^2 .

It is a cyclic number.

It is not a de Polignac number, because 216239957 - 2² = 216239953 is a prime.

It is a super-3 number, since 3×216239957³ (a number of 26 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216239953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108119978 + 108119979.

It is an arithmetic number, because the mean of its divisors is an integer number (108119979).

Almost surely, 2^216239957 is an apocalyptic number.

It is an amenable number.

216239957 is a deficient number, since it is larger than the sum of its proper divisors (1).

216239957 is an equidigital number, since it uses as much as digits as its factorization.

216239957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 44.

The square root of 216239957 is about 14705.0996936437. The cubic root of 216239957 is about 600.2221001831. Note that the first 3 decimals are identical.

The spelling of 216239957 in words is "two hundred sixteen million, two hundred thirty-nine thousand, nine hundred fifty-seven".