39709421 has 2 divisors, whose sum is σ = 39709422. Its totient is φ = 39709420.

The previous prime is 39709403. The next prime is 39709447. The reversal of 39709421 is 12490793.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23629321 + 16080100 = 4861^2 + 4010^2 .

It is a cyclic number.

It is not a de Polignac number, because 39709421 - 2¹⁰ = 39708397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39709451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19854710 + 19854711.

It is an arithmetic number, because the mean of its divisors is an integer number (19854711).

Almost surely, 2^39709421 is an apocalyptic number.

It is an amenable number.

39709421 is a deficient number, since it is larger than the sum of its proper divisors (1).

39709421 is an equidigital number, since it uses as much as digits as its factorization.

39709421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 39709421 is about 6301.5411607003. The cubic root of 39709421 is about 341.1650373713.

The spelling of 39709421 in words is "thirty-nine million, seven hundred nine thousand, four hundred twenty-one".