51517409 has 2 divisors, whose sum is σ = 51517410. Its totient is φ = 51517408.

The previous prime is 51517393. The next prime is 51517421. The reversal of 51517409 is 90471515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49350625 + 2166784 = 7025^2 + 1472^2 .

It is a cyclic number.

It is not a de Polignac number, because 51517409 - 2⁴ = 51517393 is a prime.

It is not a weakly prime, because it can be changed into another prime (51517909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25758704 + 25758705.

It is an arithmetic number, because the mean of its divisors is an integer number (25758705).

Almost surely, 2^51517409 is an apocalyptic number.

It is an amenable number.

51517409 is a deficient number, since it is larger than the sum of its proper divisors (1).

51517409 is an equidigital number, since it uses as much as digits as its factorization.

51517409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6300, while the sum is 32.

The square root of 51517409 is about 7177.5628872201. The cubic root of 51517409 is about 372.0928608697.

The spelling of 51517409 in words is "fifty-one million, five hundred seventeen thousand, four hundred nine".