39861971 has 4 divisors (see below), whose sum is σ = 39883752. Its totient is φ = 39840192.

The previous prime is 39861961. The next prime is 39861977. The reversal of 39861971 is 17916893.

39861971 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.

It is a cyclic number.

It is not a de Polignac number, because 39861971 - 2¹⁴ = 39845587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39861977) 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, 7865 + ... + 11898.

It is an arithmetic number, because the mean of its divisors is an integer number (9970938).

Almost surely, 2^39861971 is an apocalyptic number.

39861971 is a deficient number, since it is larger than the sum of its proper divisors (21781).

39861971 is a wasteful number, since it uses less digits than its factorization.

39861971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21780.

The product of its digits is 81648, while the sum is 44.

The square root of 39861971 is about 6313.6337397730. The cubic root of 39861971 is about 341.6013588706.

The spelling of 39861971 in words is "thirty-nine million, eight hundred sixty-one thousand, nine hundred seventy-one".