39018821 has 2 divisors, whose sum is σ = 39018822. Its totient is φ = 39018820.

The previous prime is 39018809. The next prime is 39018823. The reversal of 39018821 is 12881093.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37957921 + 1060900 = 6161^2 + 1030^2 .

It is a cyclic number.

It is not a de Polignac number, because 39018821 - 2¹⁸ = 38756677 is a prime.

Together with 39018823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39018823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19509410 + 19509411.

It is an arithmetic number, because the mean of its divisors is an integer number (19509411).

Almost surely, 2^39018821 is an apocalyptic number.

It is an amenable number.

39018821 is a deficient number, since it is larger than the sum of its proper divisors (1).

39018821 is an equidigital number, since it uses as much as digits as its factorization.

39018821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 39018821 is about 6246.5047026317. The cubic root of 39018821 is about 339.1756876570.

The spelling of 39018821 in words is "thirty-nine million, eighteen thousand, eight hundred twenty-one".