1809709440 has 256 divisors, whose sum is σ = 7192419840. Its totient is φ = 376012800.

The previous prime is 1809709427. The next prime is 1809709471. The reversal of 1809709440 is 449079081.

It is a super-2 number, since 2×1809709440² = 6550096514450227200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1809709392 and 1809709401.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 141720 + ... + 153960.

It is an arithmetic number, because the mean of its divisors is an integer number (28095390).

Almost surely, 2^1809709440 is an apocalyptic number.

1809709440 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 1809709440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3596209920).

1809709440 is an abundant number, since it is smaller than the sum of its proper divisors (5382710400).

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

1809709440 is a wasteful number, since it uses less digits than its factorization.

1809709440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12281 (or 12269 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 1809709440 is about 42540.6798253154. The cubic root of 1809709440 is about 1218.6236920516.

The spelling of 1809709440 in words is "one billion, eight hundred nine million, seven hundred nine thousand, four hundred forty".