51565155511 has 2 divisors, whose sum is σ = 51565155512. Its totient is φ = 51565155510.

The previous prime is 51565155457. The next prime is 51565155553. The reversal of 51565155511 is 11555156515.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51565155511 - 2³⁵ = 17205417143 is a prime.

It is a super-2 number, since 2×51565155511² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51565155311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25782577755 + 25782577756.

It is an arithmetic number, because the mean of its divisors is an integer number (25782577756).

Almost surely, 2^51565155511 is an apocalyptic number.

51565155511 is a deficient number, since it is larger than the sum of its proper divisors (1).

51565155511 is an equidigital number, since it uses as much as digits as its factorization.

51565155511 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93750, while the sum is 40.

The spelling of 51565155511 in words is "fifty-one billion, five hundred sixty-five million, one hundred fifty-five thousand, five hundred eleven".