1821274220 has 24 divisors (see below), whose sum is σ = 3825738000. Its totient is φ = 728307392.

The previous prime is 1821274187. The next prime is 1821274249. The reversal of 1821274220 is 224721281.

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, 76511 + ... + 97449.

It is an arithmetic number, because the mean of its divisors is an integer number (159405750).

Almost surely, 2^1821274220 is an apocalyptic number.

1821274220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1821274220 is an abundant number, since it is smaller than the sum of its proper divisors (2004463780).

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

1821274220 is a wasteful number, since it uses less digits than its factorization.

1821274220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25297 (or 25295 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 29.

The square root of 1821274220 is about 42676.3894911460. The cubic root of 1821274220 is about 1221.2140159401.

The spelling of 1821274220 in words is "one billion, eight hundred twenty-one million, two hundred seventy-four thousand, two hundred twenty".