229742021 has 2 divisors, whose sum is σ = 229742022. Its totient is φ = 229742020.

The previous prime is 229742017. The next prime is 229742027. The reversal of 229742021 is 120247922.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 181980100 + 47761921 = 13490^2 + 6911^2 .

It is a cyclic number.

It is not a de Polignac number, because 229742021 - 2² = 229742017 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_12629090 and since 229742021 and 12629090 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (229742027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114871010 + 114871011.

It is an arithmetic number, because the mean of its divisors is an integer number (114871011).

Almost surely, 2^229742021 is an apocalyptic number.

It is an amenable number.

229742021 is a deficient number, since it is larger than the sum of its proper divisors (1).

229742021 is an equidigital number, since it uses as much as digits as its factorization.

229742021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 229742021 is about 15157.2431860151. The cubic root of 229742021 is about 612.4634067268.

Adding to 229742021 its reverse (120247922), we get a palindrome (349989943).

The spelling of 229742021 in words is "two hundred twenty-nine million, seven hundred forty-two thousand, twenty-one".