29447221 has 2 divisors, whose sum is σ = 29447222. Its totient is φ = 29447220.

The previous prime is 29447219. The next prime is 29447233. The reversal of 29447221 is 12274492.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26152996 + 3294225 = 5114^2 + 1815^2 .

It is a cyclic number.

It is not a de Polignac number, because 29447221 - 2¹ = 29447219 is a prime.

Together with 29447219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (29447261) 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, 14723610 + 14723611.

It is an arithmetic number, because the mean of its divisors is an integer number (14723611).

Almost surely, 2^29447221 is an apocalyptic number.

It is an amenable number.

29447221 is a deficient number, since it is larger than the sum of its proper divisors (1).

29447221 is an equidigital number, since it uses as much as digits as its factorization.

29447221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 31.

The square root of 29447221 is about 5426.5293696800. The cubic root of 29447221 is about 308.8029486248.

The spelling of 29447221 in words is "twenty-nine million, four hundred forty-seven thousand, two hundred twenty-one".