216590401 has 2 divisors, whose sum is σ = 216590402. Its totient is φ = 216590400.

The previous prime is 216590393. The next prime is 216590417. The reversal of 216590401 is 104095612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 213130801 + 3459600 = 14599^2 + 1860^2 .

It is a cyclic number.

It is not a de Polignac number, because 216590401 - 2³ = 216590393 is a prime.

It is a super-2 number, since 2×216590401² = 93822803610681602, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216590401.

It is not a weakly prime, because it can be changed into another prime (216590201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108295200 + 108295201.

It is an arithmetic number, because the mean of its divisors is an integer number (108295201).

Almost surely, 2^216590401 is an apocalyptic number.

It is an amenable number.

216590401 is a deficient number, since it is larger than the sum of its proper divisors (1).

216590401 is an equidigital number, since it uses as much as digits as its factorization.

216590401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 216590401 is about 14717.0105999826. The cubic root of 216590401 is about 600.5461702718.

The spelling of 216590401 in words is "two hundred sixteen million, five hundred ninety thousand, four hundred one".