66740671 has 4 divisors (see below), whose sum is σ = 66776472. Its totient is φ = 66704872.

The previous prime is 66740669. The next prime is 66740683. The reversal of 66740671 is 17604766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17604766 = 2 ⋅8802383.

It is a cyclic number.

It is not a de Polignac number, because 66740671 - 2¹ = 66740669 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66740671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66746671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14941 + ... + 18886.

It is an arithmetic number, because the mean of its divisors is an integer number (16694118).

Almost surely, 2^66740671 is an apocalyptic number.

66740671 is a deficient number, since it is larger than the sum of its proper divisors (35801).

66740671 is a wasteful number, since it uses less digits than its factorization.

66740671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35800.

The product of its (nonzero) digits is 42336, while the sum is 37.

The square root of 66740671 is about 8169.4963737063. The cubic root of 66740671 is about 405.6301139903.

The spelling of 66740671 in words is "sixty-six million, seven hundred forty thousand, six hundred seventy-one".