1253666 has 4 divisors (see below), whose sum is σ = 1880502. Its totient is φ = 626832.

The previous prime is 1253627. The next prime is 1253683. The reversal of 1253666 is 6663521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6663521 = 139 ⋅47939.

It can be written as a sum of positive squares in only one way, i.e., 863041 + 390625 = 929^2 + 625^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 313415 + ... + 313418.

2^1253666 is an apocalyptic number.

1253666 is a deficient number, since it is larger than the sum of its proper divisors (626836).

1253666 is an equidigital number, since it uses as much as digits as its factorization.

1253666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626835.

The product of its digits is 6480, while the sum is 29.

The square root of 1253666 is about 1119.6722734801. The cubic root of 1253666 is about 107.8269404868.

The spelling of 1253666 in words is "one million, two hundred fifty-three thousand, six hundred sixty-six".