1821417229 has 2 divisors, whose sum is σ = 1821417230. Its totient is φ = 1821417228.

The previous prime is 1821417211. The next prime is 1821417337. The reversal of 1821417229 is 9227141281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1235874025 + 585543204 = 35155^2 + 24198^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1821417229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1821417629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910708614 + 910708615.

It is an arithmetic number, because the mean of its divisors is an integer number (910708615).

Almost surely, 2^1821417229 is an apocalyptic number.

It is an amenable number.

1821417229 is a deficient number, since it is larger than the sum of its proper divisors (1).

1821417229 is an equidigital number, since it uses as much as digits as its factorization.

1821417229 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 37.

The square root of 1821417229 is about 42678.0649631635. The cubic root of 1821417229 is about 1221.2459789146.

The spelling of 1821417229 in words is "one billion, eight hundred twenty-one million, four hundred seventeen thousand, two hundred twenty-nine".