1640266 has 4 divisors (see below), whose sum is σ = 2460402. Its totient is φ = 820132.

The previous prime is 1640263. The next prime is 1640267. The reversal of 1640266 is 6620461.

It is a happy number.

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., 1625625 + 14641 = 1275^2 + 121^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1640266.

It is not an unprimeable number, because it can be changed into a prime (1640263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410065 + ... + 410068.

2^1640266 is an apocalyptic number.

1640266 is a deficient number, since it is larger than the sum of its proper divisors (820136).

1640266 is an equidigital number, since it uses as much as digits as its factorization.

1640266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820135.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 1640266 is about 1280.7286988274. The cubic root of 1640266 is about 117.9337462028.

The spelling of 1640266 in words is "one million, six hundred forty thousand, two hundred sixty-six".