2012821309 has 2 divisors, whose sum is σ = 2012821310. Its totient is φ = 2012821308.

The previous prime is 2012821277. The next prime is 2012821367. The reversal of 2012821309 is 9031282102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1885470084 + 127351225 = 43422^2 + 11285^2 .

It is a cyclic number.

It is not a de Polignac number, because 2012821309 - 2⁵ = 2012821277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2012828309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1006410654 + 1006410655.

It is an arithmetic number, because the mean of its divisors is an integer number (1006410655).

Almost surely, 2^2012821309 is an apocalyptic number.

It is an amenable number.

2012821309 is a deficient number, since it is larger than the sum of its proper divisors (1).

2012821309 is an equidigital number, since it uses as much as digits as its factorization.

2012821309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 2012821309 is about 44864.4771394920. The cubic root of 2012821309 is about 1262.6076233319.

The spelling of 2012821309 in words is "two billion, twelve million, eight hundred twenty-one thousand, three hundred nine".