51121009 has 2 divisors, whose sum is σ = 51121010. Its totient is φ = 51121008.

The previous prime is 51120943. The next prime is 51121033. The reversal of 51121009 is 90012115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48608784 + 2512225 = 6972^2 + 1585^2 .

It is a cyclic number.

It is not a de Polignac number, because 51121009 - 2¹¹ = 51118961 is a prime.

It is a super-2 number, since 2×51121009² = 5226715122356162, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51127009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25560504 + 25560505.

It is an arithmetic number, because the mean of its divisors is an integer number (25560505).

Almost surely, 2^51121009 is an apocalyptic number.

It is an amenable number.

51121009 is a deficient number, since it is larger than the sum of its proper divisors (1).

51121009 is an equidigital number, since it uses as much as digits as its factorization.

51121009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90, while the sum is 19.

The square root of 51121009 is about 7149.8957335055. The cubic root of 51121009 is about 371.1360481176.

The spelling of 51121009 in words is "fifty-one million, one hundred twenty-one thousand, nine".