1821818880 has 360 divisors, whose sum is σ = 7238099232. Its totient is φ = 415236096.

The previous prime is 1821818849. The next prime is 1821818893. The reversal of 1821818880 is 888181281.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5160784 + ... + 5161136.

Almost surely, 2^1821818880 is an apocalyptic number.

1821818880 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 1821818880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3619049616).

1821818880 is an abundant number, since it is smaller than the sum of its proper divisors (5416280352).

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

1821818880 is an equidigital number, since it uses as much as digits as its factorization.

1821818880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399 (or 370 counting only the distinct ones).

The product of its (nonzero) digits is 65536, while the sum is 45.

The square root of 1821818880 is about 42682.7702943471. The cubic root of 1821818880 is about 1221.3357402663.

The spelling of 1821818880 in words is "one billion, eight hundred twenty-one million, eight hundred eighteen thousand, eight hundred eighty".