39608209021 has 2 divisors, whose sum is σ = 39608209022. Its totient is φ = 39608209020.

The previous prime is 39608208973. The next prime is 39608209027. The reversal of 39608209021 is 12090280693.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33851952121 + 5756256900 = 183989^2 + 75870^2 .

It is a cyclic number.

It is not a de Polignac number, because 39608209021 - 2¹¹ = 39608206973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39608209027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19804104510 + 19804104511.

It is an arithmetic number, because the mean of its divisors is an integer number (19804104511).

Almost surely, 2^39608209021 is an apocalyptic number.

It is an amenable number.

39608209021 is a deficient number, since it is larger than the sum of its proper divisors (1).

39608209021 is an equidigital number, since it uses as much as digits as its factorization.

39608209021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 40.

The spelling of 39608209021 in words is "thirty-nine billion, six hundred eight million, two hundred nine thousand, twenty-one".