38221728 has 24 divisors (see below), whose sum is σ = 100332288. Its totient is φ = 12740544.

The previous prime is 38221723. The next prime is 38221741. The reversal of 38221728 is 82712283.

It is a tau number, because it is divible by the number of its divisors (24).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (38221721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198976 + ... + 199167.

It is an arithmetic number, because the mean of its divisors is an integer number (4180512).

Almost surely, 2^38221728 is an apocalyptic number.

It is an amenable number.

38221728 is an abundant number, since it is smaller than the sum of its proper divisors (62110560).

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

38221728 is a wasteful number, since it uses less digits than its factorization.

38221728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398156 (or 398148 counting only the distinct ones).

The product of its digits is 10752, while the sum is 33.

The square root of 38221728 is about 6182.3723601867. The cubic root of 38221728 is about 336.8501712844.

The spelling of 38221728 in words is "thirty-eight million, two hundred twenty-one thousand, seven hundred twenty-eight".