666567743 has 4 divisors (see below), whose sum is σ = 669045960. Its totient is φ = 664089528.

The previous prime is 666567659. The next prime is 666567749. The reversal of 666567743 is 347765666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 347765666 = 2 ⋅173882833.

It is a cyclic number.

It is not a de Polignac number, because 666567743 - 2²⁴ = 649790527 is a prime.

It is a super-2 number, since 2×666567743² = 888625112016228098, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 666567691 and 666567700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666567749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1238705 + ... + 1239242.

It is an arithmetic number, because the mean of its divisors is an integer number (167261490).

Almost surely, 2^666567743 is an apocalyptic number.

666567743 is a deficient number, since it is larger than the sum of its proper divisors (2478217).

666567743 is a wasteful number, since it uses less digits than its factorization.

666567743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2478216.

The product of its digits is 3810240, while the sum is 50.

The square root of 666567743 is about 25817.9732550795. The cubic root of 666567743 is about 873.5372537076.

The spelling of 666567743 in words is "six hundred sixty-six million, five hundred sixty-seven thousand, seven hundred forty-three".