66551255513 has 2 divisors, whose sum is σ = 66551255514. Its totient is φ = 66551255512.

The previous prime is 66551255509. The next prime is 66551255539. The reversal of 66551255513 is 31555215566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60667138249 + 5884117264 = 246307^2 + 76708^2 .

It is a cyclic number.

It is not a de Polignac number, because 66551255513 - 2² = 66551255509 is a prime.

It is a super-2 number, since 2×66551255513² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66551255543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33275627756 + 33275627757.

It is an arithmetic number, because the mean of its divisors is an integer number (33275627757).

Almost surely, 2^66551255513 is an apocalyptic number.

It is an amenable number.

66551255513 is a deficient number, since it is larger than the sum of its proper divisors (1).

66551255513 is an equidigital number, since it uses as much as digits as its factorization.

66551255513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 675000, while the sum is 44.

The spelling of 66551255513 in words is "sixty-six billion, five hundred fifty-one million, two hundred fifty-five thousand, five hundred thirteen".