66170072051491 has 2 divisors, whose sum is σ = 66170072051492. Its totient is φ = 66170072051490.

The previous prime is 66170072051467. The next prime is 66170072051617. The reversal of 66170072051491 is 19415027007166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66170072051491 - 2⁵ = 66170072051459 is a prime.

It is not a weakly prime, because it can be changed into another prime (66170072051441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33085036025745 + 33085036025746.

It is an arithmetic number, because the mean of its divisors is an integer number (33085036025746).

Almost surely, 2^{66170072051491} is an apocalyptic number.

66170072051491 is a deficient number, since it is larger than the sum of its proper divisors (1).

66170072051491 is an equidigital number, since it uses as much as digits as its factorization.

66170072051491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 49.

The spelling of 66170072051491 in words is "sixty-six trillion, one hundred seventy billion, seventy-two million, fifty-one thousand, four hundred ninety-one".