1221006 has 16 divisors (see below), whose sum is σ = 2456784. Its totient is φ = 404544.

The previous prime is 1220993. The next prime is 1221019. The reversal of 1221006 is 6001221.

It is an interprime number because it is at equal distance from previous prime (1220993) and next prime (1221019).

It is a junction number, because it is equal to n+sod(n) for n = 1220982 and 1221000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 666 + ... + 1698.

It is an arithmetic number, because the mean of its divisors is an integer number (153549).

2^1221006 is an apocalyptic number.

1221006 is the 591-st nonagonal number.

1221006 is an abundant number, since it is smaller than the sum of its proper divisors (1235778).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221006 is a wasteful number, since it uses less digits than its factorization.

1221006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1235.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1221006 is about 1104.9914026815. The cubic root of 1221006 is about 106.8823349160.

Adding to 1221006 its reverse (6001221), we get a palindrome (7222227).

It can be divided in two parts, 122 and 1006, that added together give a triangular number (1128 = T₄₇).

The spelling of 1221006 in words is "one million, two hundred twenty-one thousand, six".