1279778512320 has 2688 divisors, whose sum is σ = 6127071068160. Its totient is φ = 248314429440.

The previous prime is 1279778512319. The next prime is 1279778512349. The reversal of 1279778512320 is 232158779721.

1279778512320 is a `hidden beast` number, since 1 + 2 + 7 + 97 + 7 + 8 + 512 + 32 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 10076996097 + ... + 10076996223.

It is an arithmetic number, because the mean of its divisors is an integer number (2279416320).

Almost surely, 2^{1279778512320} is an apocalyptic number.

1279778512320 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 1279778512320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3063535534080).

1279778512320 is an abundant number, since it is smaller than the sum of its proper divisors (4847292555840).

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

1279778512320 is a wasteful number, since it uses less digits than its factorization.

1279778512320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211 (or 172 counting only the distinct ones).

The product of its (nonzero) digits is 2963520, while the sum is 54.

The spelling of 1279778512320 in words is "one trillion, two hundred seventy-nine billion, seven hundred seventy-eight million, five hundred twelve thousand, three hundred twenty".