51565511 has 2 divisors, whose sum is σ = 51565512. Its totient is φ = 51565510.

The previous prime is 51565483. The next prime is 51565519. The reversal of 51565511 is 11556515.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51565511 - 2⁶ = 51565447 is a prime.

It is a super-2 number, since 2×51565511² = 5318003849382242, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51565519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25782755 + 25782756.

It is an arithmetic number, because the mean of its divisors is an integer number (25782756).

Almost surely, 2^51565511 is an apocalyptic number.

51565511 is a deficient number, since it is larger than the sum of its proper divisors (1).

51565511 is an equidigital number, since it uses as much as digits as its factorization.

51565511 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3750, while the sum is 29.

The square root of 51565511 is about 7180.9129642407. The cubic root of 51565511 is about 372.2086330163.

The spelling of 51565511 in words is "fifty-one million, five hundred sixty-five thousand, five hundred eleven".