66131256551 has 2 divisors, whose sum is σ = 66131256552. Its totient is φ = 66131256550.

The previous prime is 66131256547. The next prime is 66131256601. The reversal of 66131256551 is 15565213166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66131256551 - 2² = 66131256547 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66131256499 and 66131256508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66131256511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33065628275 + 33065628276.

It is an arithmetic number, because the mean of its divisors is an integer number (33065628276).

Almost surely, 2^66131256551 is an apocalyptic number.

66131256551 is a deficient number, since it is larger than the sum of its proper divisors (1).

66131256551 is an equidigital number, since it uses as much as digits as its factorization.

66131256551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162000, while the sum is 41.

The spelling of 66131256551 in words is "sixty-six billion, one hundred thirty-one million, two hundred fifty-six thousand, five hundred fifty-one".