1286871840 has 384 divisors, whose sum is σ = 4729777920. Its totient is φ = 326467584.

The previous prime is 1286871829. The next prime is 1286871847. The reversal of 1286871840 is 481786821.

It is a super-3 number, since 3×1286871840³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1286871847) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13266672 + ... + 13266768.

It is an arithmetic number, because the mean of its divisors is an integer number (12317130).

Almost surely, 2^1286871840 is an apocalyptic number.

1286871840 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 1286871840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2364888960).

1286871840 is an abundant number, since it is smaller than the sum of its proper divisors (3442906080).

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

1286871840 is a wasteful number, since it uses less digits than its factorization.

1286871840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 172032, while the sum is 45.

The square root of 1286871840 is about 35872.9959719006. The cubic root of 1286871840 is about 1087.7066052171.

The spelling of 1286871840 in words is "one billion, two hundred eighty-six million, eight hundred seventy-one thousand, eight hundred forty".