40320221 has 2 divisors, whose sum is σ = 40320222. Its totient is φ = 40320220.

The previous prime is 40320211. The next prime is 40320229. The reversal of 40320221 is 12202304.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35868121 + 4452100 = 5989^2 + 2110^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40320221 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40320196 and 40320205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40320229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20160110 + 20160111.

It is an arithmetic number, because the mean of its divisors is an integer number (20160111).

Almost surely, 2^40320221 is an apocalyptic number.

It is an amenable number.

40320221 is a deficient number, since it is larger than the sum of its proper divisors (1).

40320221 is an equidigital number, since it uses as much as digits as its factorization.

40320221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 40320221 is about 6349.8205486454. The cubic root of 40320221 is about 342.9053817956.

Adding to 40320221 its reverse (12202304), we get a palindrome (52522525).

The spelling of 40320221 in words is "forty million, three hundred twenty thousand, two hundred twenty-one".