1280857644864 has 1120 divisors, whose sum is σ = 4815157248000. Its totient is φ = 335240156160.

The previous prime is 1280857644853. The next prime is 1280857644901. The reversal of 1280857644864 is 4684467580821.

It is a happy number.

1280857644864 is a `hidden beast` number, since 1 + 2 + 8 + 0 + 85 + 76 + 4 + 486 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1047307357 + ... + 1047308579.

Almost surely, 2^{1280857644864} is an apocalyptic number.

1280857644864 is a gapful number since it is divisible by the number (14) 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 1280857644864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2407578624000).

1280857644864 is an abundant number, since it is smaller than the sum of its proper divisors (3534299603136).

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

1280857644864 is a wasteful number, since it uses less digits than its factorization.

1280857644864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1318 (or 1285 counting only the distinct ones).

The product of its (nonzero) digits is 82575360, while the sum is 63.

The spelling of 1280857644864 in words is "one trillion, two hundred eighty billion, eight hundred fifty-seven million, six hundred forty-four thousand, eight hundred sixty-four".