6640474 has 4 divisors (see below), whose sum is σ = 9960714. Its totient is φ = 3320236.

The previous prime is 6640463. The next prime is 6640477. The reversal of 6640474 is 4740466.

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

It can be written as a sum of positive squares in only one way, i.e., 4558225 + 2082249 = 2135^2 + 1443^2 .

It is not an unprimeable number, because it can be changed into a prime (6640477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1660117 + ... + 1660120.

Almost surely, 2^6640474 is an apocalyptic number.

6640474 is a deficient number, since it is larger than the sum of its proper divisors (3320240).

6640474 is a wasteful number, since it uses less digits than its factorization.

6640474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3320239.

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 6640474 is about 2576.9117175410. The cubic root of 6640474 is about 187.9603998379.

The spelling of 6640474 in words is "six million, six hundred forty thousand, four hundred seventy-four".