1051665840 has 120 divisors (see below), whose sum is σ = 3555910800. Its totient is φ = 278533632.

The previous prime is 1051665829. The next prime is 1051665863. The reversal of 1051665840 is 485661501.

1051665840 is a `hidden beast` number, since 1 + 0 + 516 + 65 + 84 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×1051665840² = 2212002078045811200, which contains 22 as substring.

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 = 1051665795 and 1051665804.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 102379 + ... + 112181.

It is an arithmetic number, because the mean of its divisors is an integer number (29632590).

Almost surely, 2^1051665840 is an apocalyptic number.

1051665840 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 1051665840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1777955400).

1051665840 is an abundant number, since it is smaller than the sum of its proper divisors (2504244960).

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

1051665840 is a wasteful number, since it uses less digits than its factorization.

1051665840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9971 (or 9962 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 1051665840 is about 32429.3977742418. The cubic root of 1051665840 is about 1016.9335819232.

The spelling of 1051665840 in words is "one billion, fifty-one million, six hundred sixty-five thousand, eight hundred forty".