4891616221 has 2 divisors, whose sum is σ = 4891616222. Its totient is φ = 4891616220.

The previous prime is 4891616203. The next prime is 4891616239. The reversal of 4891616221 is 1226161984.

It is a balanced prime because it is at equal distance from previous prime (4891616203) and next prime (4891616239).

It can be written as a sum of positive squares in only one way, i.e., 4642923321 + 248692900 = 68139^2 + 15770^2 .

It is a cyclic number.

It is not a de Polignac number, because 4891616221 - 2¹⁵ = 4891583453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4891676221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2445808110 + 2445808111.

It is an arithmetic number, because the mean of its divisors is an integer number (2445808111).

Almost surely, 2^4891616221 is an apocalyptic number.

It is an amenable number.

4891616221 is a deficient number, since it is larger than the sum of its proper divisors (1).

4891616221 is an equidigital number, since it uses as much as digits as its factorization.

4891616221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 40.

The square root of 4891616221 is about 69940.0902272795. The cubic root of 4891616221 is about 1697.5300024846.

The spelling of 4891616221 in words is "four billion, eight hundred ninety-one million, six hundred sixteen thousand, two hundred twenty-one".