4091689728 has 270 divisors, whose sum is σ = 14196150276. Its totient is φ = 1168763904.

The previous prime is 4091689699. The next prime is 4091689747. The reversal of 4091689728 is 8279861904.

4091689728 is a `hidden beast` number, since 409 + 168 + 9 + 72 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1014051 + ... + 1018077.

Almost surely, 2^4091689728 is an apocalyptic number.

4091689728 is a gapful number since it is divisible by the number (48) 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 4091689728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7098075138).

4091689728 is an abundant number, since it is smaller than the sum of its proper divisors (10104460548).

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

4091689728 is an equidigital number, since it uses as much as digits as its factorization.

4091689728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4069 (or 4039 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The square root of 4091689728 is about 63966.3171364430. The cubic root of 4091689728 is about 1599.4385696872.

The spelling of 4091689728 in words is "four billion, ninety-one million, six hundred eighty-nine thousand, seven hundred twenty-eight".