39528221 has 4 divisors (see below), whose sum is σ = 39553212. Its totient is φ = 39503232.

The previous prime is 39528197. The next prime is 39528239. The reversal of 39528221 is 12282593.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12282593 = 2903 ⋅4231.

It can be written as a sum of positive squares in 2 ways, for example, as 19404025 + 20124196 = 4405^2 + 4486^2 .

It is a cyclic number.

It is not a de Polignac number, because 39528221 - 2⁶ = 39528157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39528241) 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, 9950 + ... + 13343.

It is an arithmetic number, because the mean of its divisors is an integer number (9888303).

Almost surely, 2^39528221 is an apocalyptic number.

It is an amenable number.

39528221 is a deficient number, since it is larger than the sum of its proper divisors (24991).

39528221 is a wasteful number, since it uses less digits than its factorization.

39528221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24990.

The product of its digits is 8640, while the sum is 32.

The square root of 39528221 is about 6287.1472863295. The cubic root of 39528221 is about 340.6453170947.

The spelling of 39528221 in words is "thirty-nine million, five hundred twenty-eight thousand, two hundred twenty-one".