1811843940 has 96 divisors (see below), whose sum is σ = 5158782720. Its totient is φ = 475047936.

The previous prime is 1811843903. The next prime is 1811843977. The reversal of 1811843940 is 493481181.

It is an interprime number because it is at equal distance from previous prime (1811843903) and next prime (1811843977).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2491857 + ... + 2492583.

It is an arithmetic number, because the mean of its divisors is an integer number (53737320).

Almost surely, 2^1811843940 is an apocalyptic number.

1811843940 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 1811843940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2579391360).

1811843940 is an abundant number, since it is smaller than the sum of its proper divisors (3346938780).

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

1811843940 is a wasteful number, since it uses less digits than its factorization.

1811843940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381 (or 1379 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 39.

The square root of 1811843940 is about 42565.7601835090. The cubic root of 1811843940 is about 1219.1026142884.

The spelling of 1811843940 in words is "one billion, eight hundred eleven million, eight hundred forty-three thousand, nine hundred forty".