4081521906 has 96 divisors (see below), whose sum is σ = 11393907840. Its totient is φ = 1060123680.

The previous prime is 4081521901. The next prime is 4081521923. The reversal of 4081521906 is 6091251804.

4081521906 is a `hidden beast` number, since 40 + 8 + 1 + 521 + 90 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (4081521901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1120 + ... + 90356.

It is an arithmetic number, because the mean of its divisors is an integer number (118686540).

Almost surely, 2^4081521906 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 4081521906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5696953920).

4081521906 is an abundant number, since it is smaller than the sum of its proper divisors (7312385934).

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

4081521906 is a wasteful number, since it uses less digits than its factorization.

4081521906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89277 (or 89260 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 4081521906 is about 63886.7897612644. The cubic root of 4081521906 is about 1598.1126059757.

The spelling of 4081521906 in words is "four billion, eighty-one million, five hundred twenty-one thousand, nine hundred six".