51199409 has 2 divisors, whose sum is σ = 51199410. Its totient is φ = 51199408.

The previous prime is 51199397. The next prime is 51199417. The reversal of 51199409 is 90499115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29669809 + 21529600 = 5447^2 + 4640^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51199409 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (51199429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25599704 + 25599705.

It is an arithmetic number, because the mean of its divisors is an integer number (25599705).

Almost surely, 2^51199409 is an apocalyptic number.

It is an amenable number.

51199409 is a deficient number, since it is larger than the sum of its proper divisors (1).

51199409 is an equidigital number, since it uses as much as digits as its factorization.

51199409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14580, while the sum is 38.

The square root of 51199409 is about 7155.3762304997. The cubic root of 51199409 is about 371.3256779445.

The spelling of 51199409 in words is "fifty-one million, one hundred ninety-nine thousand, four hundred nine".