849640221 has 6 divisors (see below), whose sum is σ = 1227258110. Its totient is φ = 566426808.

The previous prime is 849640123. The next prime is 849640223. The reversal of 849640221 is 122046948.

849640221 is a `hidden beast` number, since 8 + 4 + 9 + 640 + 2 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 845064900 + 4575321 = 29070^2 + 2139^2 .

It is not a de Polignac number, because 849640221 - 2¹⁷ = 849509149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (849640223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47202226 + ... + 47202243.

Almost surely, 2^849640221 is an apocalyptic number.

It is an amenable number.

849640221 is a deficient number, since it is larger than the sum of its proper divisors (377617889).

849640221 is a wasteful number, since it uses less digits than its factorization.

849640221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94404475 (or 94404472 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 849640221 is about 29148.5886622320. The cubic root of 849640221 is about 947.1345684350.

The spelling of 849640221 in words is "eight hundred forty-nine million, six hundred forty thousand, two hundred twenty-one".