66747643 has 2 divisors, whose sum is σ = 66747644. Its totient is φ = 66747642.

The previous prime is 66747613. The next prime is 66747649. The reversal of 66747643 is 34674766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66747643 - 2¹³ = 66739451 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66747643.

It is not a weakly prime, because it can be changed into another prime (66747649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33373821 + 33373822.

It is an arithmetic number, because the mean of its divisors is an integer number (33373822).

Almost surely, 2^66747643 is an apocalyptic number.

66747643 is a deficient number, since it is larger than the sum of its proper divisors (1).

66747643 is an equidigital number, since it uses as much as digits as its factorization.

66747643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 43.

The square root of 66747643 is about 8169.9230718532. The cubic root of 66747643 is about 405.6442380851.

The spelling of 66747643 in words is "sixty-six million, seven hundred forty-seven thousand, six hundred forty-three".