51511203517 has 2 divisors, whose sum is σ = 51511203518. Its totient is φ = 51511203516.

The previous prime is 51511203503. The next prime is 51511203577. The reversal of 51511203517 is 71530211515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51332152356 + 179051161 = 226566^2 + 13381^2 .

It is a cyclic number.

It is not a de Polignac number, because 51511203517 - 2¹⁵ = 51511170749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51511203577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25755601758 + 25755601759.

It is an arithmetic number, because the mean of its divisors is an integer number (25755601759).

Almost surely, 2^51511203517 is an apocalyptic number.

It is an amenable number.

51511203517 is a deficient number, since it is larger than the sum of its proper divisors (1).

51511203517 is an equidigital number, since it uses as much as digits as its factorization.

51511203517 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5250, while the sum is 31.

The spelling of 51511203517 in words is "fifty-one billion, five hundred eleven million, two hundred three thousand, five hundred seventeen".