215212009 has 2 divisors, whose sum is σ = 215212010. Its totient is φ = 215212008.

The previous prime is 215212007. The next prime is 215212021. The reversal of 215212009 is 900212512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 151659225 + 63552784 = 12315^2 + 7972^2 .

It is a cyclic number.

It is not a de Polignac number, because 215212009 - 2¹ = 215212007 is a prime.

Together with 215212007, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (215212001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107606004 + 107606005.

It is an arithmetic number, because the mean of its divisors is an integer number (107606005).

Almost surely, 2^215212009 is an apocalyptic number.

It is an amenable number.

215212009 is a deficient number, since it is larger than the sum of its proper divisors (1).

215212009 is an equidigital number, since it uses as much as digits as its factorization.

215212009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 215212009 is about 14670.1059641708. The cubic root of 215212009 is about 599.2694896557.

It can be divided in two parts, 2152 and 12009, that added together give a square (14161 = 119²).

The spelling of 215212009 in words is "two hundred fifteen million, two hundred twelve thousand, nine".