815209229 has 2 divisors, whose sum is σ = 815209230. Its totient is φ = 815209228.

The previous prime is 815209223. The next prime is 815209237. The reversal of 815209229 is 922902518.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 529092004 + 286117225 = 23002^2 + 16915^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-815209229 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 815209192 and 815209201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (815209223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407604614 + 407604615.

It is an arithmetic number, because the mean of its divisors is an integer number (407604615).

Almost surely, 2^815209229 is an apocalyptic number.

It is an amenable number.

815209229 is a deficient number, since it is larger than the sum of its proper divisors (1).

815209229 is an equidigital number, since it uses as much as digits as its factorization.

815209229 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 815209229 is about 28551.8690981869. The cubic root of 815209229 is about 934.1637900986.

The spelling of 815209229 in words is "eight hundred fifteen million, two hundred nine thousand, two hundred twenty-nine".