51509429 has 2 divisors, whose sum is σ = 51509430. Its totient is φ = 51509428.

The previous prime is 51509389. The next prime is 51509441. The reversal of 51509429 is 92490515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51509329 + 100 = 7177^2 + 10^2 .

It is a cyclic number.

It is not a de Polignac number, because 51509429 - 2²⁰ = 50460853 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51509459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25754714 + 25754715.

It is an arithmetic number, because the mean of its divisors is an integer number (25754715).

Almost surely, 2^51509429 is an apocalyptic number.

It is an amenable number.

51509429 is a deficient number, since it is larger than the sum of its proper divisors (1).

51509429 is an equidigital number, since it uses as much as digits as its factorization.

51509429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 51509429 is about 7177.0069666958. The cubic root of 51509429 is about 372.0736475952.

The spelling of 51509429 in words is "fifty-one million, five hundred nine thousand, four hundred twenty-nine".