39621971 has 4 divisors (see below), whose sum is σ = 39799872. Its totient is φ = 39444072.

The previous prime is 39621941. The next prime is 39621979. The reversal of 39621971 is 17912693.

It is a happy number.

39621971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17912693 = 2281 ⋅7853.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39621971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39621979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88616 + ... + 89061.

It is an arithmetic number, because the mean of its divisors is an integer number (9949968).

Almost surely, 2^39621971 is an apocalyptic number.

39621971 is a deficient number, since it is larger than the sum of its proper divisors (177901).

39621971 is a wasteful number, since it uses less digits than its factorization.

39621971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177900.

The product of its digits is 20412, while the sum is 38.

The square root of 39621971 is about 6294.5985574936. The cubic root of 39621971 is about 340.9144099394.

The spelling of 39621971 in words is "thirty-nine million, six hundred twenty-one thousand, nine hundred seventy-one".