1278785667456 has 320 divisors, whose sum is σ = 4179531906000. Its totient is φ = 384904949760.

The previous prime is 1278785667449. The next prime is 1278785667461. The reversal of 1278785667456 is 6547665878721.

1278785667456 is a `hidden beast` number, since 1 + 2 + 7 + 8 + 7 + 8 + 566 + 7 + 4 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 16955526 + ... + 17030778.

Almost surely, 2^{1278785667456} is an apocalyptic number.

1278785667456 is a gapful number since it is divisible by the number (16) 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 1278785667456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2089765953000).

1278785667456 is an abundant number, since it is smaller than the sum of its proper divisors (2900746238544).

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

1278785667456 is a wasteful number, since it uses less digits than its factorization.

1278785667456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75439 (or 75418 counting only the distinct ones).

The product of its digits is 948326400, while the sum is 72.

The spelling of 1278785667456 in words is "one trillion, two hundred seventy-eight billion, seven hundred eighty-five million, six hundred sixty-seven thousand, four hundred fifty-six".