1220900 has 36 divisors (see below), whose sum is σ = 2747220. Its totient is φ = 470400.

The previous prime is 1220897. The next prime is 1220903. The reversal of 1220900 is 90221.

It is an interprime number because it is at equal distance from previous prime (1220897) and next prime (1220903).

It can be written as a sum of positive squares in 6 ways, for example, as 268324 + 952576 = 518^2 + 976^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220903) by changing a digit.

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 in 11 ways as a sum of consecutive naturals, for example, 2690 + ... + 3110.

2^1220900 is an apocalyptic number.

1220900 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 1220900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1373610).

1220900 is an abundant number, since it is smaller than the sum of its proper divisors (1526320).

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

1220900 is a wasteful number, since it uses less digits than its factorization.

1220900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464 (or 457 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1220900 is about 1104.9434374664. The cubic root of 1220900 is about 106.8792418776.

The spelling of 1220900 in words is "one million, two hundred twenty thousand, nine hundred".