1099820 has 24 divisors (see below), whose sum is σ = 2333184. Its totient is φ = 435456.

The previous prime is 1099817. The next prime is 1099823. The reversal of 1099820 is 289901.

It is an interprime number because it is at equal distance from previous prime (1099817) and next prime (1099823).

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1099823) 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 7 ways as a sum of consecutive naturals, for example, 2324 + ... + 2756.

It is an arithmetic number, because the mean of its divisors is an integer number (97216).

2^1099820 is an apocalyptic number.

1099820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1099820 is an abundant number, since it is smaller than the sum of its proper divisors (1233364).

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

1099820 is a wasteful number, since it uses less digits than its factorization.

1099820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569 (or 567 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 1099820 is about 1048.7230330264. The cubic root of 1099820 is about 103.2223806197. Note that the first 3 decimals are identical.

The spelling of 1099820 in words is "one million, ninety-nine thousand, eight hundred twenty".