1281609792 has 168 divisors, whose sum is σ = 3759327000. Its totient is φ = 417374208.

The previous prime is 1281609779. The next prime is 1281609799. The reversal of 1281609792 is 2979061821.

It can be written as a sum of positive squares in 4 ways, for example, as 126697536 + 1154912256 = 11256^2 + 33984^2 .

It is not an unprimeable number, because it can be changed into a prime (1281609799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8601334 + ... + 8601482.

Almost surely, 2^1281609792 is an apocalyptic number.

1281609792 is a gapful number since it is divisible by the number (12) 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 1281609792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1879663500).

1281609792 is an abundant number, since it is smaller than the sum of its proper divisors (2477717208).

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

1281609792 is a wasteful number, since it uses less digits than its factorization.

1281609792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 413 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 1281609792 is about 35799.5780980726. The cubic root of 1281609792 is about 1086.2220275977. Note that the first 3 decimals are identical.

It can be divided in two parts, 1281609 and 792, that added together give a triangular number (1282401 = T₁₆₀₁).

The spelling of 1281609792 in words is "one billion, two hundred eighty-one million, six hundred nine thousand, seven hundred ninety-two".