1226639 has 4 divisors (see below), whose sum is σ = 1266240. Its totient is φ = 1187040.

The previous prime is 1226629. The next prime is 1226651. The reversal of 1226639 is 9366221.

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

It is a cyclic number.

It is not a de Polignac number, because 1226639 - 2⁴ = 1226623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1226609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19754 + ... + 19815.

It is an arithmetic number, because the mean of its divisors is an integer number (316560).

2^1226639 is an apocalyptic number.

1226639 is a deficient number, since it is larger than the sum of its proper divisors (39601).

1226639 is an equidigital number, since it uses as much as digits as its factorization.

1226639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39600.

The product of its digits is 3888, while the sum is 29.

The square root of 1226639 is about 1107.5373582864. The cubic root of 1226639 is about 107.0464467757.

The spelling of 1226639 in words is "one million, two hundred twenty-six thousand, six hundred thirty-nine".