666440234 has 8 divisors (see below), whose sum is σ = 999770148. Its totient is φ = 333183520.

The previous prime is 666440221. The next prime is 666440261. The reversal of 666440234 is 432044666.

It can be written as a sum of positive squares in 2 ways, for example, as 462379009 + 204061225 = 21503^2 + 14285^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 666440194 and 666440203.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24254 + ... + 43830.

Almost surely, 2^666440234 is an apocalyptic number.

666440234 is a deficient number, since it is larger than the sum of its proper divisors (333329914).

666440234 is a wasteful number, since it uses less digits than its factorization.

666440234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36600.

The product of its (nonzero) digits is 82944, while the sum is 35.

The square root of 666440234 is about 25815.5037525902. The cubic root of 666440234 is about 873.4815499596.

The spelling of 666440234 in words is "six hundred sixty-six million, four hundred forty thousand, two hundred thirty-four".