1286449920 has 648 divisors, whose sum is σ = 5398048656. Its totient is φ = 281788416.

The previous prime is 1286449919. The next prime is 1286449921. The reversal of 1286449920 is 299446821.

It is an interprime number because it is at equal distance from previous prime (1286449919) and next prime (1286449921).

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

It is not an unprimeable number, because it can be changed into a prime (1286449921) 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 71 ways as a sum of consecutive naturals, for example, 24272614 + ... + 24272666.

It is an arithmetic number, because the mean of its divisors is an integer number (8330322).

Almost surely, 2^1286449920 is an apocalyptic number.

1286449920 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 1286449920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2699024328).

1286449920 is an abundant number, since it is smaller than the sum of its proper divisors (4111598736).

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

1286449920 is a wasteful number, since it uses less digits than its factorization.

1286449920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 1286449920 is about 35867.1147431739. The cubic root of 1286449920 is about 1087.5877186477.

The spelling of 1286449920 in words is "one billion, two hundred eighty-six million, four hundred forty-nine thousand, nine hundred twenty".