66256619293493 has 2 divisors, whose sum is σ = 66256619293494. Its totient is φ = 66256619293492.

The previous prime is 66256619293477. The next prime is 66256619293507. The reversal of 66256619293493 is 39439291665266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49632912673969 + 16623706619524 = 7045063^2 + 4077218^2 .

It is a cyclic number.

It is not a de Polignac number, because 66256619293493 - 2⁴ = 66256619293477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66256619293453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33128309646746 + 33128309646747.

It is an arithmetic number, because the mean of its divisors is an integer number (33128309646747).

Almost surely, 2^{66256619293493} is an apocalyptic number.

It is an amenable number.

66256619293493 is a deficient number, since it is larger than the sum of its proper divisors (1).

66256619293493 is an equidigital number, since it uses as much as digits as its factorization.

66256619293493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 680244480, while the sum is 71.

The spelling of 66256619293493 in words is "sixty-six trillion, two hundred fifty-six billion, six hundred nineteen million, two hundred ninety-three thousand, four hundred ninety-three".