666746858 has 4 divisors (see below), whose sum is σ = 1000120290. Its totient is φ = 333373428.

The previous prime is 666746849. The next prime is 666746867. The reversal of 666746858 is 858647666.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (666746849) and next prime (666746867).

It can be written as a sum of positive squares in only one way, i.e., 503239489 + 163507369 = 22433^2 + 12787^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166686713 + ... + 166686716.

Almost surely, 2^666746858 is an apocalyptic number.

666746858 is a deficient number, since it is larger than the sum of its proper divisors (333373432).

666746858 is a wasteful number, since it uses less digits than its factorization.

666746858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333373431.

The product of its digits is 11612160, while the sum is 56.

The square root of 666746858 is about 25821.4418265131. The cubic root of 666746858 is about 873.6154901231.

The spelling of 666746858 in words is "six hundred sixty-six million, seven hundred forty-six thousand, eight hundred fifty-eight".