40221728 has 48 divisors (see below), whose sum is σ = 84750624. Its totient is φ = 18723840.

The previous prime is 40221691. The next prime is 40221737. The reversal of 40221728 is 82712204.

It is a junction number, because it is equal to n+sod(n) for n = 40221697 and 40221706.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 57863 + ... + 58553.

It is an arithmetic number, because the mean of its divisors is an integer number (1765638).

Almost surely, 2^40221728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40221728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42375312).

40221728 is an abundant number, since it is smaller than the sum of its proper divisors (44528896).

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

40221728 is a wasteful number, since it uses less digits than its factorization.

40221728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825 (or 817 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 40221728 is about 6342.0602330788. The cubic root of 40221728 is about 342.6259412169.

The spelling of 40221728 in words is "forty million, two hundred twenty-one thousand, seven hundred twenty-eight".