666741 has 4 divisors (see below), whose sum is σ = 888992. Its totient is φ = 444492.

The previous prime is 666737. The next prime is 666749. The reversal of 666741 is 147666.

666741 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 666741 - 2² = 666737 is a prime.

It is a super-2 number, since 2×666741² = 889087122162, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 666699 and 666708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666749) 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, 111121 + ... + 111126.

It is an arithmetic number, because the mean of its divisors is an integer number (222248).

2⁶⁶⁶⁷⁴¹ is an apocalyptic number.

It is an amenable number.

666741 is a deficient number, since it is larger than the sum of its proper divisors (222251).

666741 is a wasteful number, since it uses less digits than its factorization.

666741 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222250.

The product of its digits is 6048, while the sum is 30.

The square root of 666741 is about 816.5420993433. The cubic root of 666741 is about 87.3612931604.

The spelling of 666741 in words is "six hundred sixty-six thousand, seven hundred forty-one".