51509389 has 2 divisors, whose sum is σ = 51509390. Its totient is φ = 51509388.

The previous prime is 51509377. The next prime is 51509429. The reversal of 51509389 is 98390515.

51509389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (51509429) can be obtained adding 51509389 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51408900 + 100489 = 7170^2 + 317^2 .

It is a cyclic number.

It is not a de Polignac number, because 51509389 - 2⁷ = 51509261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51509309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25754694 + 25754695.

It is an arithmetic number, because the mean of its divisors is an integer number (25754695).

Almost surely, 2^51509389 is an apocalyptic number.

It is an amenable number.

51509389 is a deficient number, since it is larger than the sum of its proper divisors (1).

51509389 is an equidigital number, since it uses as much as digits as its factorization.

51509389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48600, while the sum is 40.

The square root of 51509389 is about 7177.0041800183. The cubic root of 51509389 is about 372.0735512831.

The spelling of 51509389 in words is "fifty-one million, five hundred nine thousand, three hundred eighty-nine".