1286204640 has 192 divisors, whose sum is σ = 4648928256. Its totient is φ = 292810752.

The previous prime is 1286204611. The next prime is 1286204641. The reversal of 1286204640 is 464026821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1286204641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1051069 + ... + 1052291.

It is an arithmetic number, because the mean of its divisors is an integer number (24213168).

Almost surely, 2^1286204640 is an apocalyptic number.

1286204640 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 1286204640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2324464128).

1286204640 is an abundant number, since it is smaller than the sum of its proper divisors (3362723616).

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

1286204640 is a wasteful number, since it uses less digits than its factorization.

1286204640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1561 (or 1553 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 33.

The square root of 1286204640 is about 35863.6952920359. The cubic root of 1286204640 is about 1087.5185928913.

The spelling of 1286204640 in words is "one billion, two hundred eighty-six million, two hundred four thousand, six hundred forty".