616206391 has 2 divisors, whose sum is σ = 616206392. Its totient is φ = 616206390.

The previous prime is 616206389. The next prime is 616206419. The reversal of 616206391 is 193602616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 616206391 - 2¹ = 616206389 is a prime.

Together with 616206389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (616206091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 308103195 + 308103196.

It is an arithmetic number, because the mean of its divisors is an integer number (308103196).

Almost surely, 2^616206391 is an apocalyptic number.

616206391 is a deficient number, since it is larger than the sum of its proper divisors (1).

616206391 is an equidigital number, since it uses as much as digits as its factorization.

616206391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 616206391 is about 24823.5048089507. The cubic root of 616206391 is about 850.9591898511.

The spelling of 616206391 in words is "six hundred sixteen million, two hundred six thousand, three hundred ninety-one".