1855117440 has 768 divisors, whose sum is σ = 7790515200. Its totient is φ = 401448960.

The previous prime is 1855117427. The next prime is 1855117441. The reversal of 1855117440 is 447115581.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1855117395 and 1855117404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1855117441) by changing a digit.

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 95 ways as a sum of consecutive naturals, for example, 27688287 + ... + 27688353.

It is an arithmetic number, because the mean of its divisors is an integer number (10143900).

Almost surely, 2^1855117440 is an apocalyptic number.

1855117440 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 1855117440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3895257600).

1855117440 is an abundant number, since it is smaller than the sum of its proper divisors (5935397760).

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

1855117440 is a wasteful number, since it uses less digits than its factorization.

1855117440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 36.

The square root of 1855117440 is about 43071.0742842572. The cubic root of 1855117440 is about 1228.7319074410.

The spelling of 1855117440 in words is "one billion, eight hundred fifty-five million, one hundred seventeen thousand, four hundred forty".