39018221 has 4 divisors (see below), whose sum is σ = 42565344. Its totient is φ = 35471100.

The previous prime is 39018209. The next prime is 39018227. The reversal of 39018221 is 12281093.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39018221 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 (39018227) 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, 1773545 + ... + 1773566.

It is an arithmetic number, because the mean of its divisors is an integer number (10641336).

Almost surely, 2^39018221 is an apocalyptic number.

It is an amenable number.

39018221 is a deficient number, since it is larger than the sum of its proper divisors (3547123).

39018221 is a wasteful number, since it uses less digits than its factorization.

39018221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3547122.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 39018221 is about 6246.4566755882. The cubic root of 39018221 is about 339.1739491246.

The spelling of 39018221 in words is "thirty-nine million, eighteen thousand, two hundred twenty-one".