1220406 has 36 divisors (see below), whose sum is σ = 2749908. Its totient is φ = 360800.

The previous prime is 1220393. The next prime is 1220411. The reversal of 1220406 is 6040221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 29746 + ... + 29786.

2^1220406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1220406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1374954).

1220406 is an abundant number, since it is smaller than the sum of its proper divisors (1529502).

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

1220406 is a wasteful number, since it uses less digits than its factorization.

1220406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 1220406 is about 1104.7198739952. The cubic root of 1220406 is about 106.8648247896.

Multiplying 1220406 by its product of nonzero digits (96), we get a square (117158976 = 10824²).

Adding to 1220406 its reverse (6040221), we get a palindrome (7260627).

The spelling of 1220406 in words is "one million, two hundred twenty thousand, four hundred six".