39921243 has 16 divisors (see below), whose sum is σ = 55503360. Its totient is φ = 25500384.

The previous prime is 39921227. The next prime is 39921247. The reversal of 39921243 is 34212993.

It is not a de Polignac number, because 39921243 - 2⁴ = 39921227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (39921247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3918 + ... + 9756.

It is an arithmetic number, because the mean of its divisors is an integer number (3468960).

Almost surely, 2^39921243 is an apocalyptic number.

39921243 is a deficient number, since it is larger than the sum of its proper divisors (15582117).

39921243 is a wasteful number, since it uses less digits than its factorization.

39921243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5938.

The product of its digits is 11664, while the sum is 33.

The square root of 39921243 is about 6318.3259650005. The cubic root of 39921243 is about 341.7705875700.

The spelling of 39921243 in words is "thirty-nine million, nine hundred twenty-one thousand, two hundred forty-three".