900408221 has 2 divisors, whose sum is σ = 900408222. Its totient is φ = 900408220.

The previous prime is 900408217. The next prime is 900408227. The reversal of 900408221 is 122804009.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 519612025 + 380796196 = 22795^2 + 19514^2 .

It is a cyclic number.

It is not a de Polignac number, because 900408221 - 2² = 900408217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (900408227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 450204110 + 450204111.

It is an arithmetic number, because the mean of its divisors is an integer number (450204111).

Almost surely, 2^900408221 is an apocalyptic number.

It is an amenable number.

900408221 is a deficient number, since it is larger than the sum of its proper divisors (1).

900408221 is an equidigital number, since it uses as much as digits as its factorization.

900408221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 900408221 is about 30006.8029120065. The cubic root of 900408221 is about 965.6353377415.

The spelling of 900408221 in words is "nine hundred million, four hundred eight thousand, two hundred twenty-one".