996878221 has 2 divisors, whose sum is σ = 996878222. Its totient is φ = 996878220.

The previous prime is 996878209. The next prime is 996878227. The reversal of 996878221 is 122878699.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 714974121 + 281904100 = 26739^2 + 16790^2 .

It is a cyclic number.

It is not a de Polignac number, because 996878221 - 2⁵ = 996878189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (996878227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498439110 + 498439111.

It is an arithmetic number, because the mean of its divisors is an integer number (498439111).

Almost surely, 2^996878221 is an apocalyptic number.

It is an amenable number.

996878221 is a deficient number, since it is larger than the sum of its proper divisors (1).

996878221 is an equidigital number, since it uses as much as digits as its factorization.

996878221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 870912, while the sum is 52.

The square root of 996878221 is about 31573.3783589910. The cubic root of 996878221 is about 998.9583222843.

The spelling of 996878221 in words is "nine hundred ninety-six million, eight hundred seventy-eight thousand, two hundred twenty-one".