51387013 has 2 divisors, whose sum is σ = 51387014. Its totient is φ = 51387012.

The previous prime is 51386999. The next prime is 51387019. The reversal of 51387013 is 31078315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38663524 + 12723489 = 6218^2 + 3567^2 .

It is a cyclic number.

It is not a de Polignac number, because 51387013 - 2⁹ = 51386501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51387019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25693506 + 25693507.

It is an arithmetic number, because the mean of its divisors is an integer number (25693507).

Almost surely, 2^51387013 is an apocalyptic number.

It is an amenable number.

51387013 is a deficient number, since it is larger than the sum of its proper divisors (1).

51387013 is an equidigital number, since it uses as much as digits as its factorization.

51387013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 51387013 is about 7168.4735474158. The cubic root of 51387013 is about 371.7786601932.

The spelling of 51387013 in words is "fifty-one million, three hundred eighty-seven thousand, thirteen".