66361643 has 2 divisors, whose sum is σ = 66361644. Its totient is φ = 66361642.

The previous prime is 66361621. The next prime is 66361649. The reversal of 66361643 is 34616366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66361643 - 2¹² = 66357547 is a prime.

It is not a weakly prime, because it can be changed into another prime (66361649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33180821 + 33180822.

It is an arithmetic number, because the mean of its divisors is an integer number (33180822).

Almost surely, 2^66361643 is an apocalyptic number.

66361643 is a deficient number, since it is larger than the sum of its proper divisors (1).

66361643 is an equidigital number, since it uses as much as digits as its factorization.

66361643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 35.

The square root of 66361643 is about 8146.2655861444. The cubic root of 66361643 is about 404.8607823078.

The spelling of 66361643 in words is "sixty-six million, three hundred sixty-one thousand, six hundred forty-three".