666458749 has 16 divisors (see below), whose sum is σ = 742610880. Its totient is φ = 592992000.

The previous prime is 666458747. The next prime is 666458759. The reversal of 666458749 is 947854666.

It is a cyclic number.

It is not a de Polignac number, because 666458749 - 2¹ = 666458747 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 666458749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666458743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 154279 + ... + 158539.

It is an arithmetic number, because the mean of its divisors is an integer number (46413180).

Almost surely, 2^666458749 is an apocalyptic number.

It is an amenable number.

666458749 is a deficient number, since it is larger than the sum of its proper divisors (76152131).

666458749 is a wasteful number, since it uses less digits than its factorization.

666458749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4572.

The product of its digits is 8709120, while the sum is 55.

The square root of 666458749 is about 25815.8623524375. The cubic root of 666458749 is about 873.4896388876.

The spelling of 666458749 in words is "six hundred sixty-six million, four hundred fifty-eight thousand, seven hundred forty-nine".