1286670840 has 512 divisors, whose sum is σ = 5225472000. Its totient is φ = 245661696.

The previous prime is 1286670809. The next prime is 1286670863. The reversal of 1286670840 is 480766821.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1286670792 and 1286670801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 5383441 + ... + 5383679.

It is an arithmetic number, because the mean of its divisors is an integer number (10206000).

Almost surely, 2^1286670840 is an apocalyptic number.

1286670840 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 1286670840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2612736000).

1286670840 is an abundant number, since it is smaller than the sum of its proper divisors (3938801160).

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

1286670840 is a wasteful number, since it uses less digits than its factorization.

1286670840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319 (or 315 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 1286670840 is about 35870.1943122699. The cubic root of 1286670840 is about 1087.6499716544.

The spelling of 1286670840 in words is "one billion, two hundred eighty-six million, six hundred seventy thousand, eight hundred forty".