51720293 has 2 divisors, whose sum is σ = 51720294. Its totient is φ = 51720292.

The previous prime is 51720289. The next prime is 51720301. The reversal of 51720293 is 39202715.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49308484 + 2411809 = 7022^2 + 1553^2 .

It is a cyclic number.

It is not a de Polignac number, because 51720293 - 2² = 51720289 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51720283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25860146 + 25860147.

It is an arithmetic number, because the mean of its divisors is an integer number (25860147).

Almost surely, 2^51720293 is an apocalyptic number.

It is an amenable number.

51720293 is a deficient number, since it is larger than the sum of its proper divisors (1).

51720293 is an equidigital number, since it uses as much as digits as its factorization.

51720293 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 51720293 is about 7191.6822093304. The cubic root of 51720293 is about 372.5806752878.

The spelling of 51720293 in words is "fifty-one million, seven hundred twenty thousand, two hundred ninety-three".