72008221 has 2 divisors, whose sum is σ = 72008222. Its totient is φ = 72008220.

The previous prime is 72008203. The next prime is 72008329. The reversal of 72008221 is 12280027.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71995225 + 12996 = 8485^2 + 114^2 .

It is a cyclic number.

It is not a de Polignac number, because 72008221 - 2⁷ = 72008093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72008192 and 72008201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72008201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36004110 + 36004111.

It is an arithmetic number, because the mean of its divisors is an integer number (36004111).

Almost surely, 2^72008221 is an apocalyptic number.

It is an amenable number.

72008221 is a deficient number, since it is larger than the sum of its proper divisors (1).

72008221 is an equidigital number, since it uses as much as digits as its factorization.

72008221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 72008221 is about 8485.7657874820. The cubic root of 72008221 is about 416.0325976829.

Adding to 72008221 its reverse (12280027), we get a palindrome (84288248).

The spelling of 72008221 in words is "seventy-two million, eight thousand, two hundred twenty-one".