51812609 has 2 divisors, whose sum is σ = 51812610. Its totient is φ = 51812608.

The previous prime is 51812603. The next prime is 51812611. The reversal of 51812609 is 90621815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30283009 + 21529600 = 5503^2 + 4640^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51812609 is a prime.

Together with 51812611, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51812603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25906304 + 25906305.

It is an arithmetic number, because the mean of its divisors is an integer number (25906305).

Almost surely, 2^51812609 is an apocalyptic number.

It is an amenable number.

51812609 is a deficient number, since it is larger than the sum of its proper divisors (1).

51812609 is an equidigital number, since it uses as much as digits as its factorization.

51812609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 51812609 is about 7198.0975958930. The cubic root of 51812609 is about 372.8022176897.

The spelling of 51812609 in words is "fifty-one million, eight hundred twelve thousand, six hundred nine".