216156361 has 2 divisors, whose sum is σ = 216156362. Its totient is φ = 216156360.

The previous prime is 216156359. The next prime is 216156379. The reversal of 216156361 is 163651612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 213160000 + 2996361 = 14600^2 + 1731^2 .

It is a cyclic number.

It is not a de Polignac number, because 216156361 - 2¹ = 216156359 is a prime.

Together with 216156359, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (216156301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108078180 + 108078181.

It is an arithmetic number, because the mean of its divisors is an integer number (108078181).

Almost surely, 2^216156361 is an apocalyptic number.

It is an amenable number.

216156361 is a deficient number, since it is larger than the sum of its proper divisors (1).

216156361 is an equidigital number, since it uses as much as digits as its factorization.

216156361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 31.

The square root of 216156361 is about 14702.2570036032. The cubic root of 216156361 is about 600.1447437830.

The spelling of 216156361 in words is "two hundred sixteen million, one hundred fifty-six thousand, three hundred sixty-one".