1809897984 has 120 divisors (see below), whose sum is σ = 5240444352. Its totient is φ = 601344000.

The previous prime is 1809897977. The next prime is 1809897997. The reversal of 1809897984 is 4897989081.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2409609 + ... + 2410359.

Almost surely, 2^1809897984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1809897984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2620222176).

1809897984 is an abundant number, since it is smaller than the sum of its proper divisors (3430546368).

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

1809897984 is an equidigital number, since it uses as much as digits as its factorization.

1809897984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1298 (or 1279 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 63.

The square root of 1809897984 is about 42542.8958111692. The cubic root of 1809897984 is about 1218.6660112220. Note that the first 3 decimals are identical.

The spelling of 1809897984 in words is "one billion, eight hundred nine million, eight hundred ninety-seven thousand, nine hundred eighty-four".