1280164331520 has 640 divisors, whose sum is σ = 4832063319600. Its totient is φ = 323346235392.

The previous prime is 1280164331491. The next prime is 1280164331573. The reversal of 1280164331520 is 251334610821.

1280164331520 is a `hidden beast` number, since 1 + 2 + 8 + 0 + 1 + 643 + 3 + 1 + 5 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 252147222 + ... + 252152298.

Almost surely, 2^{1280164331520} is an apocalyptic number.

1280164331520 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 1280164331520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2416031659800).

1280164331520 is an abundant number, since it is smaller than the sum of its proper divisors (3551898988080).

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

1280164331520 is an frugal number, since it uses more digits than its factorization.

1280164331520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5143 (or 5106 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 1280164331520 in words is "one trillion, two hundred eighty billion, one hundred sixty-four million, three hundred thirty-one thousand, five hundred twenty".