1329256656 has 540 divisors, whose sum is σ = 5071571232. Its totient is φ = 329951232.

The previous prime is 1329256637. The next prime is 1329256667. The reversal of 1329256656 is 6566529231.

1329256656 is a `hidden beast` number, since 1 + 32 + 9 + 2 + 566 + 56 = 666.

Its product of digits (583200) is a multiple of the sum of its prime factors (90).

It is a zygodrome in base 6.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 78191560 + ... + 78191576.

Almost surely, 2^1329256656 is an apocalyptic number.

1329256656 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 1329256656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2535785616).

1329256656 is an abundant number, since it is smaller than the sum of its proper divisors (3742314576).

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

1329256656 is a wasteful number, since it uses less digits than its factorization.

1329256656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 42 counting only the distinct ones).

The product of its digits is 583200, while the sum is 45.

The square root of 1329256656 is about 36458.9722290687. The cubic root of 1329256656 is about 1099.5195301106.

The spelling of 1329256656 in words is "one billion, three hundred twenty-nine million, two hundred fifty-six thousand, six hundred fifty-six".