666240746 has 4 divisors (see below), whose sum is σ = 999361122. Its totient is φ = 333120372.

The previous prime is 666240737. The next prime is 666240749. The reversal of 666240746 is 647042666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 647042666 = 2 ⋅323521333.

It can be written as a sum of positive squares in only one way, i.e., 640849225 + 25391521 = 25315^2 + 5039^2 .

It is not an unprimeable number, because it can be changed into a prime (666240749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166560185 + ... + 166560188.

Almost surely, 2^666240746 is an apocalyptic number.

666240746 is a deficient number, since it is larger than the sum of its proper divisors (333120376).

666240746 is a wasteful number, since it uses less digits than its factorization.

666240746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333120375.

The product of its (nonzero) digits is 290304, while the sum is 41.

The square root of 666240746 is about 25811.6397386915. The cubic root of 666240746 is about 873.3943871166.

The spelling of 666240746 in words is "six hundred sixty-six million, two hundred forty thousand, seven hundred forty-six".