20051451209 has 2 divisors, whose sum is σ = 20051451210. Its totient is φ = 20051451208.

The previous prime is 20051451011. The next prime is 20051451239. The reversal of 20051451209 is 90215415002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16186963984 + 3864487225 = 127228^2 + 62165^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20051451209 is a prime.

It is not a weakly prime, because it can be changed into another prime (20051451239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10025725604 + 10025725605.

It is an arithmetic number, because the mean of its divisors is an integer number (10025725605).

Almost surely, 2^20051451209 is an apocalyptic number.

It is an amenable number.

20051451209 is a deficient number, since it is larger than the sum of its proper divisors (1).

20051451209 is an equidigital number, since it uses as much as digits as its factorization.

20051451209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600, while the sum is 29.

The spelling of 20051451209 in words is "twenty billion, fifty-one million, four hundred fifty-one thousand, two hundred nine".