1851065840 has 40 divisors (see below), whose sum is σ = 4634786688. Its totient is φ = 683470080.

The previous prime is 1851065837. The next prime is 1851065857. The reversal of 1851065840 is 485601581.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 1851065794 and 1851065803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 888896 + ... + 890975.

Almost surely, 2^1851065840 is an apocalyptic number.

1851065840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1851065840 is an abundant number, since it is smaller than the sum of its proper divisors (2783720848).

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

1851065840 is a wasteful number, since it uses less digits than its factorization.

1851065840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1779897 (or 1779891 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 38.

The square root of 1851065840 is about 43024.0146894731. The cubic root of 1851065840 is about 1227.8367334144.

The spelling of 1851065840 in words is "one billion, eight hundred fifty-one million, sixty-five thousand, eight hundred forty".