1278784806 has 36 divisors (see below), whose sum is σ = 2771907588. Its totient is φ = 393121872.

The previous prime is 1278784799. The next prime is 1278784811. The reversal of 1278784806 is 6084878721.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1138161 + ... + 1139283.

It is an arithmetic number, because the mean of its divisors is an integer number (76997433).

Almost surely, 2^1278784806 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1278784806, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1385953794).

1278784806 is an abundant number, since it is smaller than the sum of its proper divisors (1493122782).

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

1278784806 is an equidigital number, since it uses as much as digits as its factorization.

1278784806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2277 (or 1141 counting only the distinct ones).

The product of its (nonzero) digits is 1204224, while the sum is 51.

The square root of 1278784806 is about 35760.1007548916. The cubic root of 1278784806 is about 1085.4233395131.

The spelling of 1278784806 in words is "one billion, two hundred seventy-eight million, seven hundred eighty-four thousand, eight hundred six".