616221 has 16 divisors (see below), whose sum is σ = 945600. Its totient is φ = 396144.

The previous prime is 616219. The next prime is 616223. The reversal of 616221 is 122616.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (616219) and next prime (616223).

It is not a de Polignac number, because 616221 - 2¹ = 616219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 616194 and 616203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (616223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 390 + ... + 1176.

It is an arithmetic number, because the mean of its divisors is an integer number (59100).

2⁶¹⁶²²¹ is an apocalyptic number.

It is an amenable number.

616221 is a deficient number, since it is larger than the sum of its proper divisors (329379).

616221 is a wasteful number, since it uses less digits than its factorization.

616221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825 (or 819 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 616221 is about 784.9974522252. The cubic root of 616221 is about 85.0965914635.

Adding to 616221 its reverse (122616), we get a palindrome (738837).

The spelling of 616221 in words is "six hundred sixteen thousand, two hundred twenty-one".