66015971543 has 2 divisors, whose sum is σ = 66015971544. Its totient is φ = 66015971542.

The previous prime is 66015971509. The next prime is 66015971551. The reversal of 66015971543 is 34517951066.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66015971543 - 2¹⁰ = 66015970519 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66015971443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33007985771 + 33007985772.

It is an arithmetic number, because the mean of its divisors is an integer number (33007985772).

Almost surely, 2^66015971543 is an apocalyptic number.

66015971543 is a deficient number, since it is larger than the sum of its proper divisors (1).

66015971543 is an equidigital number, since it uses as much as digits as its factorization.

66015971543 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 680400, while the sum is 47.

The spelling of 66015971543 in words is "sixty-six billion, fifteen million, nine hundred seventy-one thousand, five hundred forty-three".