1222840 has 32 divisors (see below), whose sum is σ = 2898000. Its totient is φ = 463104.

The previous prime is 1222831. The next prime is 1222847. The reversal of 1222840 is 482221.

1222840 = T₂₂₇ + T₂₂₈ + ... + T₂₆₆.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45 + ... + 1564.

2^1222840 is an apocalyptic number.

1222840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1222840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1449000).

1222840 is an abundant number, since it is smaller than the sum of its proper divisors (1675160).

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

1222840 is a wasteful number, since it uses less digits than its factorization.

1222840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1639 (or 1635 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 1222840 is about 1105.8209620006. The cubic root of 1222840 is about 106.9358219968.

The spelling of 1222840 in words is "one million, two hundred twenty-two thousand, eight hundred forty".